US Adults' Likelihood to Participate in Dementia Prevention Drug Trials: Results from the National Poll on Healthy Aging

BACKGROUND

Recruitment to dementia prevention clinical trials is challenging, and participants are not representative of US adults at risk. A better understanding of the general public's interest in dementia prevention research participation is needed to inform future recruitment strategies.

OBJECTIVE

To examine US adults' characteristics associated with self-reported likelihood to participate in dementia prevention clinical trials.

DESIGN

We conducted a cross-sectional survey using the October 2018 wave of the University of Michigan National Poll on Healthy Aging.

SETTING

The National Poll on Healthy Aging is a nationally representative survey of adults using KnowledgePanel (Ipsos Public Affairs LLC), a probability-based panel of the civilian, noninstitutionalized US population.

PARTICIPANTS

We analyzed data from 1,028 respondents, ages 50 to 64 years, who completed a web survey module on brain health.

MEASUREMENTS

We used logistic regression models to examine associations between sociodemographic and dementia-related factors (e.g., family history) and self-reported likelihood to participate in a dementia prevention clinical trial of a new medicine ("very" or "somewhat likely" vs. "not likely" survey responses). Among respondents not likely to participate, we examined frequency of reasons endorsed for this decision, stratified by age, sex, and race and ethnicity.

RESULTS

Of the 1,028 respondents, half were female, 68% Non-Hispanic White, 13% Hispanic, and 12% Non-Hispanic Black. Twelve percent of respondents reported being very likely to participate in a dementia prevention trial, 32% somewhat likely, and 56% not likely. Factors associated with higher likelihood to participate were higher perceived risk of dementia [OR, 2.17 (95% CI, 1.61, 2.93)], a positive family history of dementia [OR, 1.75 (95% CI, 1.27, 2.43)], and having discussed dementia prevention with a doctor [OR, 2.20 (95% CI, 1.10, 4.42)]. There were no differences in likelihood to participate by sociodemographic characteristics. Among 570 respondents not likely to participate, 39% said they did not want to be a guinea pig, 23% thought dementia would not affect them, 22% thought there would be too high a chance for harm, 15% indicated study participation would take too much time, and 5% reported fear of learning information about oneself. There were no differences across age, sex, and racial and ethnic groups.

CONCLUSIONS

In this study, perceived risk of dementia, family history, and discussion of prevention with a doctor were associated with likelihood to participate in a dementia prevention clinical trial, whereas sociodemographic factors including race and ethnicity were not. Findings suggest that recruitment interventions focused on increasing knowledge of dementia risk and prevention trials and involving healthcare providers may be effective tools to improve enrollment rates, regardless of target community.

Assessing Cytoskeletal Destruction During Pyroptosis

Pyroptosis is an inflammatory form of cell death driven by the activation of caspase-1 and/or caspase-11 which cleaves and activates the pore-forming and cell-permeabilizing protein gasdermin-D. Pyroptosis is characterized by cell swelling and release of inflammatory cytosolic content, which were thought to be driven by colloid-osmotic lysis. Instead, we previously demonstrated that in vitro, pyroptotic cells do not in fact lyse. We also demonstrated that calpain cleaves vimentin, leading to loss of intermediate filaments, which in turn makes cells fragile and susceptible to rupture by extrinsic pressure. However, if, as our observations suggest, cells do not swell due to osmotic forces, what then causes cell rupture? Interestingly, in addition to intermediate filament loss, we demonstrated that other cytoskeletal networks, such as microtubules, actin, and nuclear lamina, are similarly lost during pyroptosis; however, the mechanisms driving these cytoskeletal disruptions as well as their functional significance are unclear. To facilitate the study of these processes, we present here the immunocytochemical methods by which we detected and assayed cytoskeletal destruction during pyroptosis.

Adult Acquired Flatfoot Deformity: Anatomy, Biomechanics, Staging, and Imaging Findings

Adult acquired flatfoot deformity (AAFD) is a common disorder that typically affects middle-aged and elderly women, resulting in foot pain, malalignment, and loss of function. The disorder is initiated most commonly by degeneration of the posterior tibialis tendon (PTT), which normally functions to maintain the talonavicular joint at the apex of the three arches of the foot. PTT degeneration encompasses tenosynovitis, tendinosis, tendon elongation, and tendon tearing. The malaligned foot is initially flexible but becomes rigid and constant as the disorder progresses. Tendon dysfunction commonly leads to secondary damage of the spring ligament and talocalcaneal ligaments and may be associated with injury to the deltoid ligament, plantar fascia, and other soft-tissue structures. Failure of multiple stabilizers appears to be necessary for development of the characteristic planovalgus deformity of AAFD, with a depressed plantar-flexed talus bone, hindfoot and/or midfoot valgus, and an everted flattened forefoot. AAFD also leads to gait dysfunction as the foot is unable to change shape and function adequately to accommodate the various phases of gait, which require multiple rapid transitions in foot position and tone for effective ambulation. The four-tier staging system for AAFD emphasizes physical examination findings and metrics of foot malalignment. Mild disease is managed conservatively, but surgical procedures directed at the soft tissues and/or bones become necessary and progressively more invasive as the disease progresses. Although much has been written about the imaging findings of AAFD, this article emphasizes the anatomy and function of the foot's stabilizing structures to help the radiologist better understand this disabling disorder. Online supplemental material is available for this article. ^©RSNA, 2019.

LOX-1: A potential driver of cardiovascular risk in SLE patients

Traditional cardiovascular disease (CVD) risk factors, such as hypertension, dyslipidemia and diabetes do not explain the increased CVD burden in systemic lupus erythematosus (SLE). The oxidized-LDL receptor, LOX-1, is an inflammation-induced receptor implicated in atherosclerotic plaque formation in acute coronary syndrome, and here we evaluated its role in SLE-associated CVD. SLE patients have increased sLOX-1 levels which were associated with elevated proinflammatory HDL, oxLDL and hsCRP. Interestingly, increased sLOX-1 levels were associated with patients with early disease onset, low disease activity, increased IL-8, and normal complement and hematological measures. LOX-1 was increased on patient-derived monocytes and low-density granulocytes, and activation with oxLDL and immune-complexes increased membrane LOX-1, TACE activity, sLOX-1 release, proinflammatory cytokine production by monocytes, and triggered the formation of neutrophil extracellular traps which can promote vascular injury. In conclusion, perturbations in the lipid content in SLE patients' blood activate LOX-1 and promote inflammatory responses. Increased sLOX-1 levels may be an indicator of high CVD risk, and blockade of LOX-1 may provide a therapeutic opportunity for ameliorating atherosclerosis in SLE patients.

Abstract 614: Resiquimod, a Toll-like receptor agonist promotes melanoma regression by enhancing plasmacytoid dendritic cells and T cytotoxic activity as a vaccination adjuvant and by direct tumor application

Introduction: Cancer immunotherapy is a modern strategy aiming at restoring the capacity of the immune system to target tumors in cancer patients. Toll-like receptor (TLR) agonists may enhance vaccination or direct immune activation at the tumor microenvironment. This clinical trial evaluated the biologic effects of Resiquimod, a TLR agonist that can activate both myeloid (TLR 8) and plasmacytoid (TLR 7) dendritic cells, on advanced stage melanoma. Methods: Subjects with in-transit melanoma metastases or high risk for recurrence and appropriate HLA were treated with peptide vaccination (class 1 restricted peptide GP100(g209-2m) and, if HLA-DP4+, class 2 restricted peptide MAGE-3243-258). Half of the patients were randomized to receive Resiquimod as an adjuvant applied to the GP100 vaccination site. Subjects with in-transit disease were then treated with resiquimod topically on half of the target lesions. To evaluate the T cell function, fresh PBMC and single cell tumor suspension were analyzed by flow cytometry using gp100-specific dextramer staining. RNA from the vaccination site was also analyzed using real-time PCR. Results: All patients (n=47) underwent GP100(g209-2m) vaccination, a majority (39) also received the MAGE-3243-258 peptide. Type 1 interferon pathway protein profiles of vaccination sites showed activation of plasmacytoid dendritic cells in patients with Resiquimod, but not in its absence. Nineteen subjects had in-transit disease at entry into the trial. In response to peptide vaccination alone, tumor regression was more likely in patients who received Resiquimod (group A) compared to those who did not (group B). (4/9 vs 0/10). In group A, 5 patients continued treatment with Resiquimod topically on the tumors, and all had tumor response (4PR, 1CR). In group B, 5 continued to tumoral resiquimod and 3 had regression (3 PR). Type I interferon (as measured by MxA and IRF7) IFN-gamma and TNF-alpha increased at the vaccination site 24 hrs after vaccination only at the sites where Resiquimod was applied. In blood, Resiquimod increased gp100-specific CD8 T cells frequency at week 8 (p=0.03) only in patients who received Resiquimod at the vaccination site. Conclusions: Resiquimod activates plasmacytoid dendritic cells at a peptide vaccination site and augments peptide vaccination sufficiently to mediate regression of in-transit melanoma metastasis. Resiquimod on in-transit melanoma, in vaccinated hosts, drives regression of metastases, regardless of previous exposure at vaccination site. An increased amount of cytokines such type I interferon, IFN-gamma, TNF-alpha, and T specific cytotoxic frequency were increased at the vaccination site after patients received Resiquimod.

Citation Format: Jorge A. Borin Scutti, Luis M. Vence, Richard E. Royal, Tara C. Wray, Janice N. Cormier, Jeffrey E. Lee, Anthony Lucci, Jeffrey E. Gershenwald, Merrick I. Ross, Jennifer Wargo, Karen A. Millerchip, Rodabe N. Amaria, Michael A. Davis, Adi Diab, Isabella C. Glitza, Wen Hwu, Sapna Patel, Scott E. Woodman, Willem W. Overwijk, Patrick Hwu. Resiquimod, a Toll-like receptor agonist promotes melanoma regression by enhancing plasmacytoid dendritic cells and T cytotoxic activity as a vaccination adjuvant and by direct tumor application [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 614.

Mitochondrial SLC25 proteins interact with NLRP3 to regulate inflammasome function

The NLRP3 protein is a key initiator of inflammation in humans. NLRP3 becomes activated by a multitude of danger signals, including pathogens, markers of metabolic dysfunction, and internalized particulates. Upon activation, NLRP3 nucleates formation of a multiprotein complex called the inflammasome, in which caspase-1 activity mediates processing of the pro-inflammatory cytokines IL-1β and IL-18 and induces pyroptosis, a pro-inflammatory form of cell death that serves to release the mature cytokines along with other inflammatory mediators, thus initiating the inflammatory response. While multiple regulators of the NLRP3 inflammasome have been described, specific ligand(s) of NLRP3 and its mechanism of activation remain largely unknown. We performed a proteomics screen using co-immunoprecipitation (IP) and mass spectrometry to identify cellular proteins that bind NLRP3. Using this screen, we identified multiple NLRP3 interactors, including a family of solute carrier (SLC) proteins that localize to the inner mitochondrial membrane. Co-IP experiments verified that four of these proteins, namely SLC25A1, a citrate transporter, SLC25A6, an ADP/ATP translocase, SLC25A11, a 2-oxoglutarate/malate carrier, and SLC25A13, a calcium-dependent glutamate transporter, specifically interact with NLRP3. Because of its linkage with known metabolic disease, we further assessed the role of SCL25A13 in inflammasome function. When ectopically expressed, SLC25A13 enhanced IL-1β release from cells, while CRISPR/Cas9 knockout of SLC25A13 from THP-1 macrophages partially abrogated NLRP3-dependent pyroptosis. Our studies reveal a novel role for mitochondrial SLC25 proteins in regulation of the NLRP3 inflammasome.

Congenital Zika virus infection as a silent pathology with loss of neurogenic output in the fetal brain

Zika virus (ZIKV) is a flavivirus with teratogenic effects on fetal brain, but the spectrum of ZIKV-induced brain injury is unknown, particularly when ultrasound imaging is normal. In a pregnant pigtail macaque (Macaca nemestrina) model of ZIKV infection, we demonstrate that ZIKV-induced injury to fetal brain is substantial, even in the absence of microcephaly, and may be challenging to detect in a clinical setting. A common and subtle injury pattern was identified, including (i) periventricular T2-hyperintense foci and loss of fetal noncortical brain volume, (ii) injury to the ependymal epithelium with underlying gliosis and (iii) loss of late fetal neuronal progenitor cells in the subventricular zone (temporal cortex) and subgranular zone (dentate gyrus, hippocampus) with dysmorphic granule neuron patterning. Attenuation of fetal neurogenic output demonstrates potentially considerable teratogenic effects of congenital ZIKV infection even without microcephaly. Our findings suggest that all children exposed to ZIKV in utero should receive long-term monitoring for neurocognitive deficits, regardless of head size at birth.

Dramatic enhancement of the detection limits of bioassays via ultrafast deposition of polydopamine

The ability to detect biomarkers with ultrahigh sensitivity radically transformed biology and disease diagnosis. However, owing to incompatibilities with infrastructure in current biological and medical laboratories, recent innovations in analytical technology have not received broad adoption. Here, we report a simple, universal ‘add-on’ technology (dubbed EASE) that can be directly plugged into the routine practices of current research and clinical laboratories and that converts the ordinary sensitivities of common bioassays to extraordinary ones. The assay relies on the bioconjugation capabilities and ultrafast and localized deposition of polydopamine at the target site, which permit a large number of reporter molecules to be captured and lead to detection-sensitivity enhancements exceeding 3 orders of magnitude. The application of EASE in the enzyme-linked-immunosorbent-assay-based detection of the HIV antigen in blood from patients leads to a sensitivity lower than 3 fg ml⁻¹. We also show that EASE allows for the direct visualization, in tissues, of the Zika virus and of low-abundance biomarkers related to neurological diseases and cancer immunotherapy.

MLKL Activation Triggers NLRP3-Mediated Processing and Release of IL-1β Independently of Gasdermin-D

Necroptosis is a form of programmed cell death defined by activation of the kinase receptor interacting protein kinase 3 and its downstream effector, the pseudokinase mixed lineage kinase domain-like (MLKL). Activated MLKL translocates to the cell membrane and disrupts it, leading to loss of cellular ion homeostasis. In this study, we use a system in which this event can be specifically triggered by a small-molecule ligand to show that MLKL activation is sufficient to induce the processing and release of bioactive IL-1β. MLKL activation triggers potassium efflux and assembly of the NLRP3 inflammasome, which is required for the processing and activity of IL-1β released during necroptosis. Notably, MLKL activation also causes cell membrane disruption, which allows efficient release of IL-1β independently of the recently described pyroptotic effector gasdermin-D. Taken together, our findings indicate that MLKL is an endogenous activator of the NLRP3 inflammasome, and that MLKL activation provides a mechanism for concurrent processing and release of IL-1β independently of gasdermin-D.

A survey of veterinary antimicrobial prescribing practices, Washington State 2015

Antimicrobial resistance is a growing global health issue. It is also a recognised problem in veterinary medicine. Between September and December 2015 the authors administered a cross-sectional survey to licensed veterinarians in Washington State to assess factors affecting antimicrobial prescribing practices among veterinarians in Washington State. Two hundred and three veterinarians completed the survey. The majority of respondents (166, 82 per cent) were engaged in small animal or exotic animal practice. 24 per cent of respondents reported not ordering culture and sensitivity (C/S) testing in practice. Of the 76 per cent of veterinarians who reported ordering C/S tests, 36 per cent reported ordering such testing 'often' or 'always' when treating presumptive bacterial infections. Most respondents (65 per cent) mentioned cost as the most common barrier to ordering a C/S test. Only 16 (10 per cent) respondents reported having access to or utilising a clinic-specific antibiogram. This survey demonstrated that while antimicrobials are commonly used in veterinary practice, and veterinarians are concerned about antimicrobial resistance, cost is a barrier to obtaining C/S tests to guide antimicrobial therapy. Summaries of antimicrobial resistance patterns are rarely available to the practising veterinarian. Efforts to promote antimicrobial stewardship in a 'One Health' manner should address barriers to the judicious use of antimicrobials in the veterinary practice setting.

Fetal brain lesions after subcutaneous inoculation of Zika virus in a pregnant nonhuman primate

We describe the development of fetal brain lesions after Zika virus (ZIKV) inoculation in a pregnant pigtail macaque. Periventricular lesions developed within 10 d and evolved asymmetrically in the occipital-parietal lobes. Fetal autopsy revealed ZIKV in the brain and significant cerebral white matter hypoplasia, periventricular white matter gliosis, and axonal and ependymal injury. Our observation of ZIKV-associated fetal brain lesions in a nonhuman primate provides a model for therapeutic evaluation.

In the superobese, weight loss and resolution of obesity comorbidities after biliopancreatic bypass and/or duodenal switch vary according to health insurance carrier: Medicaid vs Medicare vs Private insurance vs Self-Pay in 1681 Bariatric Outcomes Longitudinal Database patients

BACKGROUND

Differences in Medicaid vs Medicare vs Private vs Self-Pay duodenal switch (DS) results are unknown. This study identified DS outcomes variations by health insurance.

METHODS

Data from 1,681 DS patients were analyzed retrospectively: Medicaid (n = 138), Medicare (n = 313), Private insurance (n = 1,171), and Self-Pay (n = 59). General linear models included baseline and postoperative data and were modified for dichotomous variables.

RESULTS

Hypertension, obstructive sleep apnea, abdominal hernia, diabetes, and 9 other hepatobiliary, and somatic conditions were lowest in Private (P < .05). Self-Pay cholelithiasis, gastroesophageal reflux disease, back and/or musculoskeletal pain, and 3 others were lowest; asthma, angina, congestive heart failure, alcohol use, liver disease, and 3 others were highest (P < .05). Medicare had highest abdominal hernia and musculoskeletal pain, pseudotumor cerebri; lowest asthma, and polycystic ovarian syndrome (P < .05). Medicaid hypertension, sleep apnea, cholelithiasis, gastroesophageal reflux disease, diabetes, back pain, and 5 others were highest (P < .05); dyslipidemia and alcohol use were lowest.

CONCLUSIONS

Outcomes after DS vary by health insurance. These findings may facilitate management of DS patients.

Anakinra use during pregnancy in patients with cryopyrin-associated periodic syndromes (CAPS)

Objective: To describe the pregnancy course and outcome, and use of anakinra, a recombinant selective IL-1 receptor blocker, during pregnancy in patients with cryopyrin-associated periodic syndromes (CAPS), including familial cold auto-inflammatory syndrome (FCAS), Muckle-Wells syndrome (MWS) and neonatal onset multi-system inflammatory disease (NOMID). Methods: Women currently enrolled in natural history protocols (NCT00059748, and/or NCT00069329 under IND) who have been pregnant were included. Subjects underwent a structured, standardized interview with regards to maternal health, pregnancy and fetal outcomes. Medical records were reviewed. Results: Nine women (four with FCAS, one with MWS and four with NOMID) reported one to four pregnancies, each resulting in a total of fifteen FCAS, three MWS, and six NOMID pregnancies. Six births from FCAS mothers and three births from NOMID mothers occurred while patients were receiving anakinra. If a woman became pregnant while taking anakinra, the pre-pregnancy anakinra dose was continued. Anakinra dose was increased during one twin pregnancy. No preterm births or serious complications of pregnancy were observed. One fetus of the twin pregnancy had renal agenesis and suffered fetal demise. Genetic testing showed the deceased twin carried the same NLRP3 c.785T>C, p.V262A mutation as the mother. The other twin is healthy and mutation negative. Conclusions: Anakinra was continued during pregnancy in women with CAPS and provided significant, persistent CAPS symptom relief while continuing to prevent the long-term sequelae of CAPS. Anakinra was well tolerated. Although a causal relation between anakinra and renal agenesis seems unlikely, further safety data are needed.

Semi-automated object tracking methods in biological imaging

Time-lapse imaging is a rich data source offering potential kinetic information of cellular activity and behavior. Tracking and extracting measurements of objects from time-lapse datasets are challenges that result from the complexity and dynamics of each object's motion and intensity or the appearance of new objects in the field of view. A wide range of strategies for proper data sampling, object detection, image analysis, and post-analysis interpretation are available. Theory and methods for single-particle tracking, spot detection, and object linking are discussed in this unit, as well as examples with step-by-step procedures for utilizing semi-automated software and visualization tools for achieving tracking results and interpreting this output.

Effect of preweaned dairy calf housing system on antimicrobial resistance in commensal Escherichia coli

Group housing of preweaned dairy calves is a growing practice in the United States. The objective of this practice is to increase the average daily gain of calves in a healthy and humane environment while reducing labor requirements. However, feeding protocols, commingling of calves, and occurrence of disease in different calf-housing systems may affect the prevalence of antimicrobial drug-resistant bacteria. This study evaluated the effect of a group pen-housing system and individual pen-housing system on antimicrobial resistance trends in fecal Escherichia coli of preweaned dairy calves and on the prevalence of environmental Salmonella. Twelve farms from central New York participated in the study: 6 farms using an individual pen-housing system (IP), and 6 farms using a group pen-housing system (GP). A maximum of 3 fecal E. coli isolates per calf was tested for susceptibility to 12 antimicrobial drugs using a Kirby-Bauer disk diffusion assay. Calves in GP had a significantly higher proportion of E. coli resistant to ciprofloxacin and nalidixic acid, whereas calves in IP had a significantly higher proportion of E. coli resistant to ampicillin, ceftiofur, gentamycin, streptomycin, and tetracycline. Calf-housing system had an effect on resistance to individual antimicrobial drugs in E. coli, but no clear-cut advantage to either system was noted with regard to overall resistance frequency. No outstanding difference in the richness and diversity of resistant phenotypes was observed between the 2 calf-housing systems.

Effect of on-farm use of antimicrobial drugs on resistance in fecal Escherichia coli of preweaned dairy calves

Respiratory disease and diarrhea are the 2 most common diseases that result in the use of antimicrobial drugs in preweaned calves. Because the use of drugs in food animals, including dairy calves, has the potential for generating cross-resistance to drugs used in human medicine, it is vital to propose farm practices that foster the judicious use of antimicrobials while assuring animal health and productivity. The objective of this study was to use dairy farm calf treatment records to identify antimicrobial drug treatments in calves and to evaluate their effects on the prevalence of antimicrobial-resistant Escherichia coli from rectal swabs of preweaned dairy calves. Eight farms from central New York participated in the study, 3 farms using individual pen housing management and 5 farms using group pen housing management. Eligible study farms could not add antimicrobial drugs to the milk fed to preweaned calves and were required to have farm records documenting antimicrobial drug treatment of calves from birth to weaning. Three fecal E. coli isolates per calf were tested for susceptibility to 12 antimicrobial drugs using a Kirby-Bauer disk diffusion assay. A total of 473 calves were sampled, from which 1,423 commensal E. coli isolates were tested. Of the 9 antimicrobial drugs used on study farms, only enrofloxacin was significantly associated with reduced antimicrobial susceptibility of E. coli isolates, although treatment with ceftiofur was associated with reduced susceptibility to ceftriaxone. The median numbers of days from treatment with ceftiofur and enrofloxacin to rectal swab sampling of calves were 16 d (range: 1-39) and 12 d (range: 6-44), respectively. At the isolate level, treatment with enrofloxacin resulted in odds ratios of 2 [95% confidence interval (CI): 1-4] and 3 (95% CI: 2-6), respectively, for isolation of nonsusceptible E. coli to nalidixic acid and ciprofloxacin compared with calves not treated with enrofloxacin. Treatment with ceftiofur resulted in an odds ratio of 3 (95% CI: 0.9-12) for isolation of nonsusceptible E. coli to ceftriaxone compared with calves not treated with ceftiofur. Treatment with enrofloxacin resulted in selection of isolates that presented phenotypic resistance to both ciprofloxacin and ceftriaxone. Treatment with ceftiofur resulted in a higher prevalence of isolates resistant to ≥3 antimicrobial drugs (97%) compared with no treatment with ceftiofur (73%). These findings reinforce the necessity for continued implementation of practices at the dairy farm that support the sustainable and judicious use of antimicrobial drugs in dairy calves.

Cancer patient-reported outcomes assessment using wireless touch screen tablet computers

PURPOSE

To assess the feasibility of collecting patient-reported outcomes data with wireless touch screen tablet computers in the adult oncology palliative care setting.

METHODS

Patients were provided with tablet computers during scheduled clinic visits and answered online queries about their experience over the past week in the health domains of anxiety, depression, fatigue, pain interference, physical function, instrumental social support, sleep impairment, diarrhea, constipation, nausea, vomiting, anorexia, dyspnea, neuropathy, and spiritual values.

RESULTS

Content analysis of patient interviews indicates that wireless touch screen tablet computers are a feasible approach for collecting patient-reported outcome measures by palliative care cancer patients presenting in clinic. Most patients indicated that the questionnaire was easy to answer. However, all but one patient requested some form of assistance, and many reported difficulties attributable to a lack of familiarity with the device, interpretation of certain questions, and wireless connectivity-related issues.

CONCLUSIONS

This feasibility study demonstrates that tablet computers have the potential to efficiently and reliably collect patient-reported health status measures among palliative care cancer patients presenting in clinics. The use of these devices may lead to substantial improvements by making patient-reported outcomes available for clinical decision-making.

Evaluation of the pituitary gland using magnetic resonance imaging: T1-weighted vs. VIBE imaging

Volumetric interpolated breath-hold examination (VIBE) is used for abdominal imaging as a fast and efficient modality. Evaluation of brain lesions using VIBE is not common and its use for the pituitary gland has not yet been addressed. Our goal was to compare coronal T1-weighted (T1W) and VIBE images in patients undergoing studies of the pituitary gland. We hypothesized that, for this purpose, VIBE is superior to T1W images. T1W and VIBE images of the pituitary gland in 32 patients were evaluated. The two sequences were compared with specific attention to: contrast enhancement (gland and cavernous sinuses) and ability to view the anatomy of the cavernous sinuses. In patients with macroadenomas, visualization of the optic chiasm was also assessed. Images were rated as: VIBE being better, equal, or worse in comparison to T1W images. We also compared VIBE and T1W images specifically looking at micro/macro-adenomas and post-surgical patients. Statistical analysis was performed using chi-square statistics. Of the 32 patients, the VIBE sequence showed superior contrast enhancement in 18 patients, six were found as being equal to T1W, and in eight instances VIBE was found to be worse than T1W. These results were statistically significant (p=.02). When looking at micro/macro-adenomas and post-surgical patients specifically, there was a trend to VIBE being superior to T1W but these data were not statistically significant. Visualization of chiasm in macroadenomas was similar for both techniques. VIBE was significantly superior to T1W with respect to pituitary and cavernous sinus contrast enhancement and cavernous sinus anatomy. A trend towards VIBE being superior in the evaluation of adenomas (pre- and post-operative) was seen, but it was not statistically significant. This is likely due to the small population size.

The SCF-Fbw7 ubiquitin ligase degrades MED13 and MED13L and regulates CDK8 module association with Mediator

The Mediator complex is an essential transcription regulator that bridges transcription factors with RNA polymerase II. This interaction is controlled by dynamic interactions between Mediator and the CDK8 module, but the mechanisms governing CDK8 module-Mediator association remain poorly understood. We show that Fbw7, a tumor suppressor and ubiquitin ligase, binds to CDK8-Mediator and targets MED13/13L for degradation. MED13/13L physically link the CDK8 module to Mediator, and Fbw7 loss increases CDK8 module-Mediator association. Our work reveals a novel mechanism regulating CDK8 module-Mediator association and suggests an expanded role for Fbw7 in transcriptional control and an unanticipated relationship with the CDK8 oncogene.

p120-catenin is essential for terminal end bud function and mammary morphogenesis

Although p120-catenin (p120) is crucial for E-cadherin function, ablation experiments in epithelial tissues from different organ systems reveal markedly different effects. Here, we examine for the first time the consequences of p120 knockout during mouse mammary gland development. An MMTV-Cre driver was used to target knockout to the epithelium at the onset of puberty. p120 ablation was detected in approximately one-quarter of the nascent epithelium at the forth week post-partum. However, p120 null cells were essentially nonadherent, excluded from the process of terminal end bud (TEB) morphogenesis and lost altogether by week six. This elimination process caused a delay in TEB outgrowth, after which the gland developed normally from cells that had retained p120. Mechanistic studies in vitro indicate that TEB dysfunction is likely to stem from striking E-cadherin loss, failure of cell-cell adhesion and near total exclusion from the collective migration process. Our findings reveal an essential role for p120 in mammary morphogenesis.

Abstract 3995: Identification of putative miRNA targets by a systems biological approach in NCI-60 data

MicroRNAs (miRNAs) are single-stranded, non-coding RNA molecules and on average only 22 nucleotides long that regulate gene expression at the post-transcriptional level. Target predictions of miRNA based on sequence are limited due to too many candidates resulting in high false positives. To overcome this limitation functional target prediction approaches have been investigated by using mRNA and miRNA expression data. These approaches used in the computational assessment of functional miRNA-target association. However, these approaches with miRNA-mRNA association were not enough to verify real functional targets at protein level, which could affect on biological signaling pathway. Therefore, in order to overcome current limitation we developed a novel correlation-based approach (sequence-independence) that predict the association of miRNAs with signaling pathways by using genomics and proteomics data from NCI-60 cancer cell lines (mRNA, miRNA, and protein expression data). To identify miRNA-protein association, we used two correlation-based methods: direct comparison (miRNA-protein pairs) and indirect comparison (miRNA-mRNA and protein-mRNA pairs), then compared their outputs. In direct comparison, we calculated Pearson correlation coefficients for 96k probe pairs and found over 3 k significant correlated pairs (3.2 %) at the cut-off p-value &lt; 0.005: among them 53.4 % were negative and 46.6% were positive. In indirect comparison, we ranked the number of correlated mRNA probes between miRNA-mRNA and protein-mRNA pairs, in which we calculated over 11 and 5.7 million probe pairs respectively. Then, two significant output pair sets were combined by intersection of mRNA probes and then determined the number of common probes. With these determined numbers, finally we generated association score matrix between miRNA and protein probes. Using those score matrix, we evaluated the highly associated miRNAs with 40 biological pathways, which play critical roles in cell cycle, proliferation and metastasis. In conclusion, we developed a noble expression profile-based approach to systematically predict potential miRNA functional targets which play critical roles in cell signaling pathways from the NCI-60 genomic and proteomic data at whole genomic scale.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3995. doi:10.1158/1538-7445.AM2011-3995

From image to data using common image-processing techniques

A digital microscopy image is an array of number values, which with adequate contrast can be interpreted as spatial information. Through processing and analysis by mathematical means, using computer-assisted imaging software programs, raw image data contrast can be enhanced to improve the extraction of image features for measurement and analysis. This mathematical feature extraction (referred to as segmentation) provides the basis for general image processing. The methods discussed in this unit address common image analysis challenges such as object counting with touching objects, objects within other objects, and object identification in a field with uneven illumination or uneven brightness, along with step-by-step procedures for achieving these results.

Statistically reconstructing continuous isotropic and anisotropic two-phase media while preserving macroscopic material properties

We propose a method to generate statistically similar reconstructions of two-phase media. As with previous work, we initially characterize the microstructure of the material using two-point correlation functions (a subset of spatial correlation functions) and then generate numerical reconstructions using a simulated annealing method that preserves the geometric relationships of the material's phase of interest. However, in contrast to earlier contributions that consider reconstructions composed of discrete arrays of pixels or voxels alone, we generate reconstructions based on assemblies of continuous, three-dimensional, interpenetrating objects. The result is a continuum description of the material microstructure (as opposed to a discretized or pixelated description), capable of efficiently representing large disparities in scale. Different reconstruction methods are considered based on distinct combinations of two-point correlation functions of varying degrees of complexity. The quality of the reconstruction methods are evaluated by comparing the total pore fraction, specific surface area of the percolating cluster, pore fraction of the percolating cluster, tortuosity, and permeability of the reconstructions to those of a set of reference assemblies. Elsewhere it has been proposed that two-phase media could be statistically reproduced with only two spatial correlation functions: the two-point probability function (the probability that two points lie within the same phase) and the lineal path function (the probability that a line between two points lies entirely within the same phase). We find that methods employing the two-point probability function and lineal path function are improved if the percolating cluster volume is also considered in the reconstruction. However, to reproduce more complicated geometric assemblies, we find it necessary to employ the two-point probability, two-point cluster, and lineal path function in addition to the percolating cluster volume to produce a generally accurate statistical reconstruction.

Salmonella Cerro isolated over the past twenty years from various sources in the US represent a single predominant pulsed-field gel electrophoresis type

Salmonella Cerro prevalence in US dairy cattle has increased significantly during the past decade. Comparison of 237 Salmonella isolates collected from various human and animal sources between 1986 and 2009 using pulsed-field gel electrophoresis, antimicrobial resistance typing, and spvA screening, showed very limited genetic diversity, indicating clonality of this serotype. Improved subtyping methods are clearly needed to analyze the potential emergence of this serotype. Our results thus emphasize the critical importance of population-based pathogen surveillance for the detection and characterization of potentially emerging pathogens, and caution to critically evaluate the adequacy of diagnostic tests for a given study population and diagnostic application.

p120-catenin is essential for maintenance of barrier function and intestinal homeostasis in mice

Epithelial-cadherin (E-cadherin) is a master organizer of the epithelial phenotype. Its function is regulated in part by p120-catenin (referred to herein as p120), a cytoplasmic binding partner that directly regulates cadherin stability. As it has been suggested that cadherins have a role in inflammatory bowel disease (IBD), we sought to investigate this further by assessing the effect of p120 deficiency in mouse small intestine and colon. p120 conditional KO mice were superficially normal at birth but declined rapidly and died within 21 days. Cell-cell adhesion defects and inflammation led to progressive mucosal erosion and terminal bleeding, similar to what is observed in a dominant-negative cadherin mouse model of IBD. Additionally, selective loss of adherens junctions and accumulation of atypical COX-2-expressing neutrophils in p120-null areas of the colon were observed. To elucidate the mechanism, direct effects of p120 deficiency were assessed in vitro in a polarizing colon cancer cell line. Notably, transepithelial electrical resistance was dramatically reduced, neutrophil binding was increased 30 fold, and levels of COX-2, an enzyme associated with IBD, were markedly increased in neutrophils. Our data suggest that p120 loss disrupts the neonatal intestinal barrier and amplifies neutrophil engagement and that these changes lead to catastrophic inflammation during colonization of the neonatal gut with bacteria and other luminal antigens. Thus, we conclude that p120 has an essential role in barrier function and epithelial homeostasis and survival in the intestine.

Serological survey for antibodies to Leptospira in dogs and raccoons in Washington State

A high number of reported canine leptospirosis cases occurred in Washington State from 2004 to 2006. This prompted a serosurvey of healthy dogs from around the state to determine the distribution of exposure risk and to provide insight into serovar epidemiology in the region. In addition, a convenience sample of sera from injured raccoons was also tested, and clinical serological data from the Washington Animal Disease Diagnostic Laboratory were examined. The proportion of dogs with an antibody titre (>or=1:100) to any serovar was 27/158 (17.1%, 95% CI 11.6-23.9), and that proportion among raccoons was 22/115 (19.1%, 95% CI 12.4-27.5) suggesting that the potential for exposure in Washington state is not uncommon. The most frequently detected serovars in healthy dogs were Autumnalis, Icterohemorrhagiae and Canicola, in clinical canine samples Autumnalis, Bratislava and Pomona were more frequent and in sick or injured raccoons Autumnalis, and Pomona were most frequently detected. Clinical canine serology demonstrated a late summer-fall seasonality that was consistent with other reports. An outbreak of canine leptospirosis occurred during 2004-2006 and was located primarily in western Washington counties, as were three reported human cases in 2005. Canine leptospirosis surveillance is an important tool for detecting human risk of exposure and may provide insights into which serovars are currently of clinical importance.

Genetic diversity of Flavobacterium psychrophilum recovered from commercially raised rainbow trout, Oncorhynchus mykiss (Walbaum), and spawning coho salmon, O. kisutch (Walbaum)

Flavobacterium psychrophilum is the aetiological agent of rainbow trout fry syndrome and bacterial cold water disease. This study examined the genetic diversity of F. psychrophilum isolates retrieved from multiple epizootics at rainbow trout, Oncorhynchus mykiss, rearing facilities and from spawning coho salmon, O. kisutch. A total of 139 isolates were confirmed as F. psychrophilum by PCR assay and were further typed using pulsed-field gel electrophoresis (PFGE). Multiple epizootics at three proximally located rainbow trout rearing facilities were numerically dominated by three PFGE profiles, which accounted for 76% of all trout isolates. In coho salmon, 19 PFGE profiles were differentiated by PFGE and four numerically dominant PFGE profiles represented 56% of all coho salmon isolates. PFGE analysis also indicated that the average similarity of macrorestriction patterns of F. psychrophilum isolates was greater in rainbow trout than in coho salmon (88% vs. 70%). Furthermore, it was not unusual to isolate multiple PFGE profiles from a single coho salmon sample whereas only two PFGE profiles were shared between two sample dates separated by 1 month. It is clear that the domestic rainbow trout aquaculture facilities studied here were primarily affected by a complex of genetically related strains whereas spawning coho salmon supported a much more genetically diverse collection of F. psychrophilum.

Associations between bovine, human, and raw milk, and beef isolates of non-O157 Shiga toxigenic Escherichia coli within a restricted geographic area of the United States

A survey for Shiga toxigenic Escherichia coli in raw milk and beef was conducted within a defined geographic region of the United States. Prevalence rates based on detection of Shiga toxin gene (stx) were 36% for retail beef, 23% for beef carcasses, and 21% for raw milk samples, which were significantly higher than were Shiga toxigenic E. coli isolation rates of 7.5, 5.8, and 3.2%, respectively. Seasonal prevalence differences were significant for stx positivity among ground beef and milk samples. Distribution of stx subtypes among isolates varied according to sample type, with stx1 predominating in milk, stx2 on carcasses, and the combination of both stx1 and stx2 in beef. Ancillary virulence markers eae and ehx were evident in 23 and 15% of isolates, respectively. Pulsed-field gel electrophoresis demonstrated associations between food isolates and sympatric bovine fecal, and human clinical isolates. These data demonstrate that non-O157 Shiga toxigenic E. coli is present in the food chain in the Pacific Northwest, and its risk to health warrants critical assessment.

An attempt to measure the spread of emergency medicine internationally

OBJECTIVE

To determine the feasibility of using the internet to track the spread of emergency medicine internationally.

OVERVIEW

This was an attempt to perform a descriptive cross-sectional study employing a web-based survey.

SUBJECTS

Potential respondents were identified from multiple sources.

OBSERVATIONS

The primary outcome was the response to 16 questions about EM care and the setting in which it was delivered for acute cardiac, paediatric, obstetrical illnesses and trauma. The questions were divided into six general areas and elicited for urban, semi-urban and rural settings. A series of four e-mails soliciting completion of the survey were sent to potential respondents.

ANALYSIS

Simple descriptive statistics.

RESULTS

We identified 358 potential respondents with valid e-mail addresses over a period of three years. Overall, 145 (41%) responded and 117 (33% 95% CI 28-38%) of them were complete and interpretable. There was one response from 54 and two responses from 29 countries, representing an overall response rate by country surveyed of 65% (95% CI 57-73%), but of all existing countries of only 43% (95% CI 36-50%). Based on sparse data, it appears that in urban areas, 47% (obstetrics) to 65% (paediatric) of acutely sick or injured patients are taken to an ED-equivalent. For rural areas, this range was 19% (obstetrical) to 40% (trauma). CT scans are available in 78% of urban ED-equivalents but 12% of rural ones. Haematocrits are available in 72% of rural settings. In 60% of responding nations, some type of EM training was available, and in 42% physicians went abroad to study EM.

CONCLUSIONS

A survey of international EM is challenging to achieve because of difficulty in both identifying and in contacting potential respondents. Based on sparse data, population density (urban, rural) appears to be related to both the location to which acutely ill patients are taken for their care and to the level of technology available. The specialty of EM is now recognised internationally and education in EM is common.

Comparison of Salmonella enterica serotype Infantis isolates from a veterinary teaching hospital

AIMS

To compare Salmonella enterica serotype Infantis isolates obtained from patients or the environment of a veterinary teaching hospital over a period of 9 years following a nosocomial outbreak to determine whether isolates were epidemiologically related or represented unrelated introductions into the hospital environment.

METHODS AND RESULTS

Fifty-six S. Infantis isolates were compared based on their phenotypic (antimicrobial drug [AMD] susceptibility pattern) and genotypic (pulsed-field gel electrophoresis [PFGE] pattern and presence of integrons) characteristics. Epidemiologically unrelated S. Infantis isolates clustered separately from all but two of the hospital isolates, and several isolates from different years and various sources were indistinguishable from each other in cluster analysis of two-enzyme PFGE results. A high percentage of isolates (80.3%) were resistant to at least one AMD, with 67.8% showing resistance to >5 AMD. The majority (74.1%) of isolates tested contained type 1 integrons.

CONCLUSION

Results strongly suggest that there was nosocomial transmission of S. Infantis during the initial outbreak, and that contamination arising from this outbreak persisted across years despite rigorous hygiene and biosecurity precautions and may have led to subsequent nosocomial infections.

SIGNIFICANCE AND IMPACT OF THE STUDY

Evidence of persistence and transmission of Salmonella clones across years, even in the face of rigorous preventive measures, has important implications for other facilities that have experienced outbreaks of Salmonella infections.

Antimicrobial Effects of Pseudomonas aeruginosa on Survivability and Recovery of Campylobacter jejuni on Poultry Products

Three types of poultry products representing differences in skin coverage were tested to determine the ability of Pseudomonas aeruginosa to inhibit growth of Campylobacter jejuni. Processed ready-to-cook poultry carcasses were obtained from the Poultry Research Unit at Auburn University and were not subjected to any treatment to reduce or eliminate the native microflora on the carcasses. Carcasses were cut into wing sections (drumette, flat, tip), split breast pieces (with and without bone), and boneless, skinless breast pieces. Equal numbers of the 3 product types were subjected to 1 of 6 treatments: 1) uninoculated, 2) C. jejuni only, 3) P. aeruginosa type 1 only, 4) P. aeruginosa type 2 only, 5) C. jejuni + P. aeruginosa type 1, or 6) C. jejuni + P. aeruginosa type 2. Products were inoculated at 10(4) to 10(5) cfu. Postinoculation, equal numbers of product type were also subjected to the following: 1) aerobic or vacuum packaging, 2) storage temperature of 4 or 10 degrees C, and 3) storage of 0, 1, 2, 3, or 4 d. Products were sampled after storage duration to determine the population of C. jejuni and P. aeruginosa. Individual pieces were rinsed with 50 mL of buffered peptone water. The recovered rinse was used to make appropriate dilutions and spiral plated onto Campy-Cefex and Pseudomonas P agars. Campy-Cefex plates were incubated microaerophilically at 42 degrees C for 48 h, whereas Pseudomonas P plates were incubated aerobically at 37 degrees C for 24 to 48 h. Random suspect colonies on Campy-Cefex plates were confirmed by cell morphology when viewed under microscopic examination. Suspect colonies on Pseudomonas P plates produced a blue color in the medium indicative of glycerol reduction. At both 4 and 10 degrees C, neither type of P. aeruginosa inhibited the growth or survival of C. jejuni compared to plates that were inoculated with C. jejuni only.

Survival of Campylobacter jejuni on Poultry Skin and Meat at Varying Temperatures

Researchers have recently found a much higher prevalence of Campylobacter on skin-on poultry products vs. skinless products. These data suggest that contamination is associated primarily with poultry skin, and Campylobacter may not survive on skinless poultry meat. Therefore, the objective of this study was to quantify the survival of Campylobacter poultry skin vs. meat under differing storage conditions. Skin and meat were irradiated to eliminate native microflora and inoculated with Campylobacter jejuni (~5.0 x 10(5) cfu/mL). Meat and skin samples were packaged in polystyrene trays, covered with Cryovac film, and then subjected to 1 of the following storage conditions: 1) 4 degrees C for 11 d; 2) 4 degrees C for 1 d, then -3 degrees C for 10 d; 3) 4 degrees C for 1 d, -3 degrees C for 1 d, then 4 degrees C for 9 d; or 4) 4 degrees C for 1 d, -3 degrees C for 1 d, 20 degrees C for 1 h on d2, then 4 degrees for 9 d. On d 0, 2, 3, 5, 7, 9, and 11, populations of Campylobacter were determined. The experiment was replicated 3 times. In each experiment, populations of surviving Campylobacter were not affected by storage conditions (P > or = 0.05), and there was no interaction between temperature treatments and sample type. Surviving Campylobacter populations were affected (P < or = 0.05) by sample type (skin vs. meat). Campylobacter, in the absence of competing microflora, survived well on poultry skin and meat at the temperatures tested. In all experiments, higher populations were established on the inoculated skin vs. inoculated meat. These populations remained consistently 0.4 to 0.9 log(10) cfu/g higher on skin vs. meat. Poultry skin topography may account, in part, for these higher populations on skin.

High-throughput genomic technology in research and clinical management of breast cancer. Plasma-based proteomics in early detection and therapy

Protein-based breast cancer biomarkers are a promising resource for breast cancer detection at the earliest and most treatable stages of the disease. Plasma is well suited to proteomic-based methods of biomarker discovery because it is easily obtained, is routinely used in the diagnosis of many diseases, and has a rich proteome. However, due to the vast dynamic range in protein concentration and the often uncertain tissue and cellular origin of plasma proteins, proteomic analysis of plasma requires special consideration compared with tissue and cultured cells. This review briefly touches on the search for plasma-based protein biomarkers for the early detection and treatment of breast cancer.

p120-catenin and p190RhoGAP regulate cell-cell adhesion by coordinating antagonism between Rac and Rho

Integration of receptor tyrosine kinase, integrin, and cadherin activities is crucial for normal cell growth, motility, and adhesion. Here, we describe roles for p120-catenin (p120) and p190RhoGAP that coordinate crosstalk between these systems and regulate cadherin function. Surprisingly, PDGFR-induced actin remodeling in NIH3T3 cells is blocked in the absence of p120, and the cells are partially transformed via constitutive activation of Rho. We have traced the mechanism to unexpected codependent roles for p120 and p190RhoGAP in regulating Rac-dependent antagonism of Rho. Receptor-induced Rac activity causes translocation of p190RhoGAP to adherens junctions (AJs), where it couples to the cadherin complex via interaction with p120. AJ formation is dependent on this p120-p190RhoGAP interaction and fails altogether if either of these proteins are compromised. We propose that Rac activation links diverse signaling systems to AJ assembly by controlling transient p190RhoGAP interactions with p120 and localized inhibition of Rho.

Role of epidermal growth factor receptor degradation in gemcitabine-mediated cytotoxicity

We have recently reported that treatment with gemcitabine, a potent chemotherapeutic agent and radiation sensitizer, stimulates phosphorylation of the epidermal growth factor receptor (EGFR). Because phosphorylation of EGFR is known to precede receptor degradation, we hypothesized that gemcitabine treatment may also result in EGFR degradation. In two human head and neck cancer cell lines, UMSCC-1 and UMSCC-6, we demonstrated an approximately 80% decrease in total EGFR levels at 72 h after a 2-h treatment with 1 muM gemcitabine. Neither cisplatin nor 5-fluorouracil, which are used to treat head and neck cancer, caused EGFR degradation. EGFR downregulation did not occur at the level of transcription, as assessed by reverse transcription-polymerase chain reaction (RT-PCR), but instead occurred via phosphorylation and ubiquitination of the receptor along a proteosome/lysosome-mediated pathway. Inhibition of EGFR degradation, by either pretreatment with the EGFR tyrosine kinase inhibitor gefitinib or by exposure to the proteosome/lysosome inhibitor MG132, significantly reduced gemcitabine-induced cell death. These results suggest that EGFR degradation may be a novel mechanism for gemcitabine-mediated cell death. These findings also indicate that caution should be exercised when combining gemcitabine with agents that may prevent EGFR degradation, such as EGFR tyrosine kinase inhibitors administered in a suboptimal sequence or proteosome inhibitors.

Effects of elevated atmospheric carbon dioxide on biomass and carbon accumulation in a model regenerating longleaf pine community

Plant species vary in response to atmospheric CO2 concentration due to differences in physiology, morphology, phenology, and symbiotic relationships. These differences make it very difficult to predict how plant communities will respond to elevated CO2. Such information is critical to furthering our understanding of community and ecosystem responses to global climate change. To determine how a simple plant community might respond to elevated CO2, a model regenerating longleaf pine community composed of five species was exposed to two CO2 regimes (ambient, 365 micromol mol(-1) and elevated, 720 micromol mol(-1)) for 3 yr. Total above- and belowground biomass was 70 and 49% greater, respectively, in CO2-enriched plots. Carbon (C) content followed a response pattern similar to biomass, resulting in a significant increase of 13.8 Mg C ha(-1) under elevated CO2. Responses of individual species, however, varied. Longleaf pine (Pinus palustris Mill.) was primarily responsible for the positive response to CO2 enrichment. Wiregrass (Aristida stricta Michx.), rattlebox (Crotalaria rotundifolia Walt. Ex Gmel.), and butterfly weed (Asclepias tuberosa L.) exhibited negative above- and belowground biomass responses to elevated CO2, while sand post oak (Quercus margaretta Ashe) did not differ significantly between CO2 treatments. As with pine, C content followed patterns similar to biomass. Elevated CO2 resulted in alterations in community structure. Longleaf pine comprised 88% of total biomass in CO2-enriched plots, but only 76% in ambient plots. In contrast, wiregrass, rattlebox, and butterfly weed comprised 19% in ambient CO2 plots, but only 8% under high CO2. Therefore, while longleaf pine may perform well in a high CO2 world, other members of this community may not compete as well, which could alter community function. Effects of elevated CO2 on plant communities are complex, dynamic, and difficult to predict, clearly demonstrating the need for more research in this important area of global change science.

p120-catenin mediates inflammatory responses in the skin

Although p120-catenin regulates adherens junction (AJ) stability in cultured cells, genetic studies in lower eukaryotes have not revealed a role for this protein in vivo. Using conditional targeting in mice, we show that p120 null neonatal epidermis exhibits reduced intercellular AJ components but no overt disruption in barrier function or intercellular adhesion. As the mice age, however, they display epidermal hyperplasia and chronic inflammation, typified by hair degeneration and loss of body fat. Using skin engraftments and anti-inflammatory drugs, we show that these features are not attributable to reductions in junctional cadherins and catenins, but rather NFkB activation. Both in vivo and in vitro, p120 null epidermal cells activate nuclear NFkB, triggering a cascade of proinflammatory NFkB targets. Although the underlying mechanism is likely complex, we show that p120 affects NFkB activation and immune homeostasis in part through regulation of Rho GTPases. These findings provide important new insights into p120 function.

Blocked Acinar Development, E-Cadherin Reduction, and Intraepithelial Neoplasia upon Ablation of p120-Catenin in the Mouse Salivary Gland

p120 catenin is thought to be a key regulator of E-cadherin function and stability, but its role(s) in vivo is poorly understood. To examine these directly, we generated a conditional p120 knockout mouse and targeted p120 ablation to the embryonic salivary gland. Surprisingly, acinar differentiation is completely blocked, resulting in a gland composed entirely of ducts. Moreover, p120 ablation causes E-cadherin deficiency in vivo and severe defects in adhesion, cell polarity, and epithelial morphology. These changes closely phenocopy high-grade intraepithelial neoplasia, a condition that, in humans, typically progresses to invasive cancer. Tumor-like protrusions appear immediately after p120 ablation at e14 and expand into the lumen until shortly after birth, at which time the animals die with completely occluded glands. The data reveal an unexpected role for p120 in salivary acinar development and show that p120 ablation by itself induces effects consistent with a role in tumor progression.

Development of PCR assays targeting genes in O-antigen gene clusters for detection and identification of Escherichia coli O45 and O55 serogroups

The Escherichia coli O45 O-antigen gene cluster of strain O45:H2 96-3285 was sequenced, and conventional (singleplex), multiplex, and real-time PCR assays were designed to amplify regions in the wzx (O-antigen flippase) and wzy (O-antigen polymerase) genes. In addition, PCR assays targeting the E. coli O55 wzx and wzy genes were designed based on previously published sequences. PCR assays targeting E. coli O45 showed 100% specificity for this serogroup, whereas by PCR assays specific for E. coli O55, 97/102 strains serotyped as E. coli O55 were positive for wzx and 98/102 for wzy. Multiplex PCR assays targeting the E. coli O45 and the E. coli O55 wzx and wzy genes were used to detect the organisms in fecal samples spiked at levels of 10(6) and 10(8) CFU/0.2 g feces. Thus, the PCR assays can be used to detect and identify E. coli serogroups O45 and O55.

TamA interacts with LeuB, the homologue of Saccharomyces cerevisiae Leu3p, to regulate gdhA expression in Aspergillus nidulans

Previous studies have shown that expression of the gdhA gene, encoding NADP-linked glutamate dehydrogenase (NADP-GDH), in Aspergillus nidulans is regulated by the major nitrogen regulatory protein AreA and its co-activator TamA. We show here that loss of TamA function has a more severe effect on the levels of gdhA expression than loss of AreA function. Using TamA as the bait in a yeast two-hybrid screen, we have identified a second protein that interacts with TamA. Sequencing analysis and functional studies have shown that this protein, designated LeuB, is a transcriptional activator with similar function to the homologous Leu3p of Saccharomyces cerevisiae. Inactivation of leuB revealed that this gene is involved in the regulation of gdhA, and an areA; leuB double mutant was shown to have similar NADP-GDH levels to a tamA single mutant. The requirement for TamA function to promote gdhA expression is likely to be due to its dual interaction with AreA and LeuB.

Detection of Escherichia coli serogroups O26 and O113 by PCR amplification of the wzx and wzy genes

PCR-based assays for detecting enterohemorrhagic Escherichia coli serogroups O26 and O113 were developed by targeting the wzx (O-antigen flippase) and the wzy (O-antigen polymerase) genes found in the O-antigen gene cluster of each organism. The PCR assays were specific for the respective serogroups, as there was no amplification of DNA from non-O26 and non-O113 E. coli serogroups or from other bacterial genera tested. Using the PCR assays, we were able to detect the organisms in seeded apple juice inoculated at concentration levels as low as < or =10 CFU/ml. The O26- and O113-specific PCR assays can potentially be used for typing E. coli O26 and O113 serogroups; these assays will offer an advantage to food and environmental microbiology laboratories in terms of identifying these non-O157 serogroups by replacing antigen-based serotyping.

EGFR signaling to p120-catenin through phosphorylation at Y228

Epidermal growth factor receptor (EGFR) signals to p120(ctn) (p120), implying a role for EGFR in modulating cell-cell adhesion in epithelial tissues. p120 controls cadherin turnover, and may have other roles that modulate cadherin adhesiveness. To clarify the role for EGFR and other tyrosine kinases in regulating p120 function, we have generated and characterized a new phosphospecific antibody to p120 Y228, as well as a novel siRNA-based reconstitution system for analyzing roles of individual p120 phosphorylation events. In A431 cells, epidermal growth factor induced striking p120 phosphorylation at Y228. Y228-phosphorylated p120 localized to adherens junctions and lamellipodia, and was significantly enhanced in cells around the colony periphery. A screen of carcinoma cell lines revealed that some contain unusually high steady state levels of Y228 phosphorylation, suggesting that disregulated kinase activity in tumors may affect adhesion by constitutive cross talk to cadherin complexes. Despite these observations, mutation of Y228 and other prominent Src-associated p120 phosphorylation sites did not noticeably reduce the ability of E-cadherin to assemble junctions and induce compaction of cultured cells. Although A431 cells display significant activation of both EGFR and Src kinases, our data suggest that these account for only a fraction of the steady state activity that targets p120 Y228, and that Src family kinases are not necessary intermediates for epidermal growth factor-induced signaling to p120 Y228.

A core function for p120-catenin in cadherin turnover

p120-catenin stabilizes epithelial cadherin (E-cadherin) in SW48 cells, but the mechanism has not been established. Here, we show that p120 acts at the cell surface to control cadherin turnover, thereby regulating cadherin levels. p120 knockdown by siRNA expression resulted in dose-dependent elimination of epithelial, placental, neuronal, and vascular endothelial cadherins, and complete loss of cell–cell adhesion. ARVCF and δ-catenin were functionally redundant, suggesting that proper cadherin-dependent adhesion requires the presence of at least one p120 family member. The data reveal a core function of p120 in cadherin complexes, and strongly predict a dose-dependent loss of E-cadherin in tumors that partially or completely down-regulate p120.