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In the emergency department (ED), laboratory testing accounts for a significant portion of the medical assessment. Although excess laboratory test ordering has been proven to be prevalent, different types of interventions have been used to encourage a behavioural change in how physicians order tests. In one western Canadian hospital medicine program, a quality improvement project aimed to reduce the total monthly blood urea nitrogen (BUN) test ordered by physicians was found to be successful. The objective of this project was to evaluate a similar multicomponent intervention aimed at ED physician ordering, with the primary goal of reducing the number of monthly BUN tests ordered per ED visit.A pre post intervention design was conducted over 12-months. The first intervention component was an educational presentation conducted by physician leaders. Second, a regularly used order panel within the ED electronic order system was modified, removing the BUN test. The third component involved audit and feedback; the total monthly BUN test ordered for the ED department post intervention start was shared with all ED physicians twice (at 5 and 12 months).An interrupted time series analysis was completed to evaluate the multicomponent intervention effect.The total monthly ordered BUN test declined from an average of 1905 pre-intervention to 448 post-intervention, and the total monthly BUN test to total ED visit ratio declined from 0.46 to 0.1. These results were a statistically significant reduction in physician BUN test ordering.Targeted education, order panel design and data feedback interventions can impact physician ordering behaviour in the emergent healthcare context, where diagnostic tests are often over used.RéSUMé: INTRODUCTION: Dans les services d'urgence (SU), les analyses de laboratoire représentent une part importante de l'évaluation médicale. Bien qu'il ait été prouvé que la prescription excessive d'examens de laboratoire est répandue, différents types d'interventions ont été utilisés pour encourager un changement de comportement dans la façon dont les médecins commandent des examens. Dans un programme de médecine hospitalière de l'Ouest canadien, un projet d'amélioration de la qualité visant à réduire le nombre total de tests mensuels d'azote uréique du sang (BUN) demandés par les médecins s'est avéré fructueux. L'objectif de ce projet était d'évaluer une intervention similaire à plusieurs composantes visant les ordonnances des médecins des urgences, avec pour objectif principal de réduire le nombre d'analyses mensuelles de BUN commandés par visite aux urgences. MéTHODE: Une conception pré-post-intervention a été menée sur 12 mois. Le premier volet de l'intervention consistait en une présentation éducative menée par des médecins chefs de file. Deuxièmement, un panneau de commande régulièrement utilisé dans le système de commande électronique du SU a été modifié, supprimant le test BUN. Le troisième volet concernait l'audit et le retour d'information : le nombre total de tests mensuels d'azote uréique sanguin commandés pour le service des urgences après le début de l'intervention a été communiqué à tous les médecins des urgences à deux reprises (à 5 et 12 mois). Une analyse de séries chronologiques interrompues a été réalisée pour évaluer l'effet de l'intervention multicomposante. RéSULTATS: Le nombre total mensuel d'analyses BUN commandés a baissé d'une moyenne de 1905 avant l'intervention à 448 après l'intervention, et le rapport entre le nombre total mensuel de test BUN et le nombre total de visites aux urgences a baissé de 0,46 à 0,1. Ces résultats représentaient une réduction statistiquement significative des ordonnances de test BUN par les médecins. CONCLUSIONS: Des interventions ciblées en matière d'éducation, de conception de panels de commandes et de retour d'informations peuvent avoir un impact sur le comportement des médecins en matière de commandes dans le contexte des soins de santé émergents, où les tests de diagnostic sont souvent surutilisés.

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Lrig1 is the founding member of the Lrig family and has been implicated in the negative regulation of several oncogenic receptor tyrosine kinases including ErbB2. Lrig1 is expressed at low levels in several cancer types but is overexpressed in some prostate and colorectal tumors. Given this heterogeneity, whether Lrig1 functions to suppress or promote tumor growth remains a critical question. Previously, we found that Lrig1 was poorly expressed in ErbB2-positive breast cancer, suggesting that Lrig1 has a growth-inhibitory role in this tumor type. However, breast cancer is a complex disease, with ErbB2-positive tumors accounting for just 25% of all breast cancers. To gain a better understanding of the role of Lrig1 in breast cancer, we examined its expression in estrogen receptor α (ERα)-positive disease which accounts for the majority of breast cancers. We find that Lrig1 is expressed at significantly higher levels in ERα-positive disease than in ERα-negative disease. Our study provides a molecular rationale for Lrig1 enrichment in ERα-positive disease by showing that Lrig1 is a target of ERα. Estrogen stimulates Lrig1 accumulation and disruption of this induction enhances estrogen-dependent tumor cell growth, suggesting that Lrig1 functions as an estrogen-regulated growth suppressor. In addition, we find that Lrig1 expression correlates with prolonged relapse-free survival in ERα-positive breast cancer, identifying Lrig1 as a new prognostic marker in this setting. Finally, we show that ErbB2 activation antagonizes ERα-driven Lrig1 expression, providing a mechanistic explanation for Lrig1 loss in ErbB2-positive breast cancer. This work provides strong evidence for a growth-inhibitory role for Lrig1 in breast cancer. Mol Cancer Res; 9(10); 1406–17. ©2011 AACR.

Related Article from Isolating the Effects of Social Interactions on Cancer Biology

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Supplemental Tables 1, 2, 3 and 4, Supplemental Figures 1 through 7 and Supplemental Figure legends

miR-127 is downregulated in breast cancer, where it has been shown to suppress the proliferation, migration, and invasion of breast cancer cells. In triple-negative breast cancer (TNBC), miR-127 downregulation correlates with decreased disease-free and overall patient survival. Tumor suppressor miRNAs may hold therapeutic promise but progress has been limited by several factors, including the lability and high cost of miRNA mimics. Here, we take a novel approach to produce a miR-127 prodrug (miR-127PD), which we demonstrate is processed to mature, functional miR-127-3p in TNBC tumor cells. miR-127PD decreased the viability and motility of TNBC cells, sensitized TNBC cells to chemotherapy, and restricted the TNBC stem cell population. Furthermore, systemic delivery of miR-127PD suppressed tumor growth of MDA-MB-231 and MDA-MB-468 TNBC cells and spontaneous metastasis of MDA-MB-231 cells. In addition, CERK, NANOS1, FOXO6, SOX11, SOX12, FASN, and SUSD2 were identified as novel, functionally important targets of miR-127. In conclusion, our study demonstrates that miR-127 functions as a tumor and metastasis suppressor in TNBC and that delivery of miR-127 may hold promise as a novel therapy.Significance:Exogenous administration of miR-127, which is functionally activated in target cells, inhibits growth and spontaneous metastasis of triple-negative breast cancer.

mRNA Sequencing Data Matrix Table

sRNA Sequencing Data Matrix Table

Supplemental Experimental Procedures. The details of plasmid construction and siRNA synthesis

Supplemental Figure 3. Cell viability following MKP1 siRNA treatment

The aberrant expression of membrane mucins such as Muc1 and Muc4 by tumor cells has been shown to engage signaling pathways that promote cellular properties associated with tumor progression. Our previous studies have shown that Muc4 interacts with and potentiates signaling by the ErbB2 (HER2) receptor tyrosine kinase through an epidermal growth factor–like domain in its extracellular region. Here, we show that expression of Muc4 in human A375 melanoma cells and MCF7 breast cancer cells confers resistance to apoptosis induced by a variety of stimuli, including chemotherapeutic agents, the absence of serum factors, and the loss of cellular adhesion. Mapping experiments revealed that the O-glycosylation and cytosolic domains of Muc4 are dispensable for its antiapoptotic activity, and are also dispensable for the potentiation of signaling by ErbB2. Knockdown of endogenous Muc4 in JIMT-1 breast cancer cells sensitizes cells to apoptotic stimuli, and this can be rescued by Muc4 forms lacking the O-glycosylation or cytosolic domains. Surprisingly, however, the molecular mechanisms underlying Muc4 antiapoptotic activity vary among cell lines. Although Muc4 in JIMT-1 cells engages ErbB2 to promote cell survival, its antiapoptotic mechanism in MCF7 and A375 cells seems to be independent of ErbB2. However, Muc4 expression in all cell lines culminates in the phosphorylation and inactivation of the proapoptotic protein Bad and the elevation of the prosurvival protein Bcl-xL. Our observations suggest that tumor cells can exploit the versatile antiapoptotic activities of Muc4 to acquire resistance to therapeutic agents, and augment cell survival after the loss of adhesion and microenvironment-derived survival factors. [Cancer Res 2009;69(7):2845–52]

Supplementary Figure 1 from The Membrane Mucin Muc4 Inhibits Apoptosis Induced by Multiple Insults via ErbB2-Dependent and ErbB2-Independent Mechanisms

Supplemental Figure 7. Inhibition of mitochondrial localization of MKP1 upon HER2 inhibitor, Lapatinib, treatment in MCF7/C6 cells

Supplemental Figure 2. The inhibition of ERK phosphorylation by U0126

Supplemental Figure 6. Cell viability after HER2 inhibitor, Lapatinib, treatment in MCF7/C6 and SKBR3 cells

Supplemental Figure 5. Cell viability following MKP1 inhibitior, Sanguinarine, treatment in MCF7/C6 cells

Supplemental Figure 4. Cell viability following MKP1 inhibitior, Sanguinarine, treatment in SKBR3 cells

Supplemental Figure 1. Mitochondrial membrane potential of MCF7 wt, C6 and HER2 cells

Background Free Open-Access Medical education (FOAM) use among residents continues to rise. However, it often lacks quality assurance processes and residents receive little guidance on quality assessment. The Academic Life in Emergency Medicine Approved Instructional Resources tool (AAT) was created for FOAM appraisal by and for expert educators and has demonstrated validity in this context. It has yet to be evaluated in other populations. Objectives We assessed the AAT's usability in a diverse population of practicing emergency medicine (EM) physicians, residents, and medical students; solicited feedback; and developed a revised tool. Methods As part of the Medical Education Translational Resources: Impact and Quality (METRIQ) study, we recruited medical students, EM residents, and EM attendings to evaluate five FOAM posts with the AAT and provide quantitative and qualitative feedback via an online survey. Two independent analysts performed a qualitative thematic analysis with discrepancies resolved through discussion and negotiated consensus. This analysis informed development of an initial revised AAT, which was then further refined after pilot testing among the author group. The final tool was reassessed for reliability. Results Of 330 recruited international participants, 309 completed all ratings. The Best Evidence in Emergency Medicine (BEEM) score was the component most frequently reported as difficult to use. Several themes emerged from the qualitative analysis: for ease of use-understandable, logically structured, concise, and aligned with educational value. Limitations include deviation from questionnaire best practices, validity concerns, and challenges assessing evidence-based medicine. Themes supporting its use include evaluative utility and usability. The author group pilot tested the initial revised AAT, revealing a total score average measure intraclass correlation coefficient (ICC) of moderate reliability (ICC = 0.68, 95% confidence interval [CI] = 0 to 0.962). The final AAT's average measure ICC was 0.88 (95% CI = 0.77 to 0.95). Conclusions We developed the final revised AAT from usability feedback. The new score has significantly increased usability, but will need to be reassessed for reliability in a broad population.

Interleukin 22 (IL-22) is critically involved in gut immunity and host defense and primarily produced by activated T cells. In different circumstances IL-22 may contribute to pathological conditions or act as a cancer promoting cytokine secreted by infiltrating immune cells. Here we show that bone marrow-derived macrophages (BMM) express and produce IL-22 after activation of the aryl hydrocarbon receptor (AhR) when cells are activated through the Toll-like receptor (TLR) family. The additional activation of AhR triggered a significant induction of IL-22 in TLR-activated BMM. Deletion and mutation constructs of the IL-22 promoter revealed that a consensus DRE and RelBAhRE binding element are necessary to mediate the synergistic effects of AhR and TLR ligands. Inhibitor studies and analysis of BMM derived from knockout mice confirmed that the synergistic induction of IL-22 by AhR and TLR ligands depend on the expression of AhR and Nuclear Factor-kappa B (NF-κB) member RelB. The exposure to particulate matter (PM) collected from traffic related air pollution (TRAP) and wildfires activated AhR as well as NF-κB signaling and significantly induced the expression of IL-22. In summary this study shows that simultaneous activation of the AhR and NF-κB signaling pathways leads to synergistic and prolonged induction of IL-22 by integrating signals of the canonical and non-canonical AhR pathway.

Background: Clostridium difficile (CD) is often classified as a healthcare-associated infection (HAI) and a hospital-acquired condition (HAC) in the hospital setting. However, pediatric oncology pa...

Study objective Online educational resources such as blogs are increasingly used for education by emergency medicine clinicians. The Social Media Index was developed to quantify their relative impact. The Medical Education Translational Resources: Indicators of Quality (METRIQ) study was conducted in part to determine the association between the Social Media Index score and quality as measured by gestalt and previously derived quality instruments. Methods Ten blogs were randomly selected from a list of emergency medicine and critical care Web sites. The 2 most recent clinically oriented blog posts published on these blogs were evaluated with gestalt, the Academic Life in Emergency Medicine Approved Instructional Resources (ALiEM AIR) score, and the METRIQ-8 score. Volunteer raters (including medical students, emergency medicine residents, and emergency medicine attending physicians) were identified with a multimodal recruitment methodology. The Social Media Index was calculated in February 2016, November 2016, April 2017, and December 2017. Pearson's correlations were calculated between the Social Media Index and the average rater gestalt, ALiEM AIR score, and METRIQ-8 score. Results A total of 309 of 330 raters completed all ratings (93.6%). The Social Media Index correlated moderately to strongly with the mean rater gestalt ratings (range 0.69 to 0.76) and moderately with the mean rater ALiEM AIR score (range 0.55 to 0.61) and METRIQ-8 score (range 0.53 to 0.57) during the month of the blog post's selection and for 2 years after. Conclusion The Social Media Index's correlation with multiple quality evaluation instruments over time supports the hypothesis that it is associated with overall Web site quality. It can play a role in guiding individuals to high-quality resources that can be reviewed with critical appraisal techniques.

Study objective Open educational resources such as blogs are increasingly used for medical education. Gestalt is generally the evaluation method used for these resources; however, little information has been published on it. We aim to evaluate the reliability of gestalt in the assessment of emergency medicine blogs. Methods We identified 60 English-language emergency medicine Web sites that posted clinically oriented blogs between January 1, 2016, and February 24, 2016. Ten Web sites were selected with a random-number generator. Medical students, emergency medicine residents, and emergency medicine attending physicians evaluated the 2 most recent clinical blog posts from each site for quality, using a 7-point Likert scale. The mean gestalt scores of each blog post were compared between groups with Pearson's correlations. Single and average measure intraclass correlation coefficients were calculated within groups. A generalizability study evaluated variance within gestalt and a decision study calculated the number of raters required to reliably (>0.8) estimate quality. Results One hundred twenty-one medical students, 88 residents, and 100 attending physicians (93.6% of enrolled participants) evaluated all 20 blog posts. Single-measure intraclass correlation coefficients within groups were fair to poor (0.36 to 0.40). Average-measure intraclass correlation coefficients were more reliable (0.811 to 0.840). Mean gestalt ratings by attending physicians correlated strongly with those by medical students (r=0.92) and residents (r=0.99). The generalizability coefficient was 0.91 for the complete data set. The decision study found that 42 gestalt ratings were required to reliably evaluate quality (>0.8). Conclusion The mean gestalt quality ratings of blog posts between medical students, residents, and attending physicians correlate strongly, but individual ratings are unreliable. With sufficient raters, mean gestalt ratings provide a community standard for assessment.

We describe here the diversity of chloroplast proteins required for embryo development in Arabidopsis (Arabidopsis thaliana). Interfering with certain chloroplast functions has long been known to result in embryo lethality. What has not been reported before is a comprehensive screen for embryo-defective (emb) mutants altered in chloroplast proteins. From a collection of transposon and T-DNA insertion lines at the RIKEN chloroplast function database (http://rarge.psc.riken.jp/chloroplast/) that initially appeared to lack homozygotes and segregate for defective seeds, we identified 23 additional examples of EMB genes that likely encode chloroplast-localized proteins. Fourteen gene identities were confirmed with allelism tests involving duplicate mutant alleles. We then queried journal publications and the SeedGenes database (www.seedgenes.org) to establish a comprehensive dataset of 381 nuclear genes encoding chloroplast proteins of Arabidopsis associated with embryo-defective (119 genes), plant pigment (121 genes), gametophyte (three genes), and alternate (138 genes) phenotypes. Loci were ranked based on the level of certainty that the gene responsible for the phenotype had been identified and the protein product localized to chloroplasts. Embryo development is frequently arrested when amino acid, vitamin, or nucleotide biosynthesis is disrupted but proceeds when photosynthesis is compromised and when levels of chlorophyll, carotenoids, or terpenoids are reduced. Chloroplast translation is also required for embryo development, with genes encoding chloroplast ribosomal and pentatricopeptide repeat proteins well represented among EMB datasets. The chloroplast accD locus, which is necessary for fatty acid biosynthesis, is essential in Arabidopsis but not in Brassica napus or maize (Zea mays), where duplicated nuclear genes compensate for its absence or loss of function.

Eight years after publication of the Arabidopsis genome sequence and two years before completing the first phase of an international effort to characterize the function of every Arabidopsis gene, plant biologists remain unable to provide a definitive answer to the following basic question: what is the minimal gene set required for normal growth and development? The purpose of this review is to summarize different strategies employed to identify essential genes in Arabidopsis, an important component of the minimal gene set in plants, to present an overview of the datasets and specific genes identified to date, and to discuss the prospects for future saturation of this important class of genes. The long-term goal of this collaborative effort is to facilitate basic research in plant biology and complement ongoing research with other model organisms.

Background: Errors involving the mix-up of tuberculin purified protein derivative (PPD) and vaccines leading to adverse reactions and unnecessary medical management have been reported previously. Objectives: To determine the frequency of PPD-vaccine mix-ups reported to the US Vaccine Adverse Event Reporting System (VAERS) and the Adverse Event Reporting System (AERS), characterize adverse events and clusters involving mix-ups and describe reported contributory factors. Methods: We reviewed AERS reports from 1969 to 2005 and VAERS reports from 1990 to 2005. We defined a mix-up error event as an incident in which a single patient or a cluster of patients inadvertently received vaccine instead of a PPD product or received a PPD product instead of vaccine. We defined a cluster as inadvertent administration of PPD or vaccine products to more than one patient in the same facility within 1 month. Results: Of 115 mix-up events identified, 101 involved inadvertent administration of vaccines instead of PPD. Product confusion involved PPD and multiple vaccines. The annual number of reported mix-ups increased from an average of one event per year in the early 1990s to an average of ten events per year in the early part of this decade. More than 240 adults and children were affected and the majority reported local injection site reactions. Four individuals were hospitalized (all recovered) after receiving the wrong products. Several patients were inappropriately started on tuberculosis prophylaxis as a result of a vaccine local reaction being interpreted as a positive tuberculin skin test. Reported potential contributory factors involved both system factors (e.g. similar packaging) and human errors (e.g. failure to read label before product administration). Conclusions: To prevent PPD-vaccine mix-ups, proper storage, handling and administration of vaccine and PPD products is necessary.

The biosynthesis of histidine (His) in microorganisms, long studied through the isolation and characterization of auxotrophic mutants, has emerged as a paradigm for the regulation of metabolism and gene expression. Much less is known about His biosynthesis in flowering plants. One limiting factor has been the absence of large collections of informative auxotrophs. We describe here the results of a systematic screen for His auxotrophs of Arabidopsis (Arabidopsis thaliana). Ten insertion mutants disrupted in four different biosynthetic genes (HISN2, HISN3, HISN4, HISN6A) were identified through a combination of forward and reverse genetics and were shown to exhibit an embryo-defective phenotype that could be rescued by watering heterozygous plants with His. Male transmission of the mutant allele was in several cases reduced. Knockouts of two redundant genes (HISN1B and HISN5A) had no visible phenotype. Another mutant blocked in the final step of His biosynthesis (hisn8) and a double mutant altered in the redundant first step of the pathway (hisn1a hisn1b) exhibited a combination of gametophytic and embryonic lethality in heterozygotes. Homozygous mutant seedlings and callus tissue produced from rescued seeds appeared normal when grown in the presence of His but typically senesced after continued growth in the absence of His. These knockout mutants document the importance of His biosynthesis for plant growth and development, provide valuable insights into amino acid transport and source-sink relationships during seed development, and represent a significant addition to the limited collection of well-characterized auxotrophs in flowering plants.

A real-time PCR assay for the detection of four Leishmania complexes (L. Viannia, L. mexicana, L. donovani/infantum, and L. major) was developed and evaluated. The assay was developed to detect the glucosephosphate isomerase gene and capitalizes on DNA sequence variability within that gene for Leishmania complex identification. Primer/probe sets were created and tested against a panel of 21 known negative controls and on DNA extracted from cultured promastigotes or from tissue biopsies from patients with cutaneous leishmaniasis. The assay was highly specific, as no amplification products were detected in the negative control samples while simultaneously retaining a high degree of complex-specific diagnostic accuracy for cultured organisms and patient clinical samples. Real-time PCR offers rapid (within hours) identification of Leishmania to the complex level and provides a useful molecular tool to assist both epidemiologists and clinicians.

Alpha contracting is a collaborative effort between a buyer and supplier during contract formation to maximize efficiency and effectiveness. Although several benefits of Alpha contracting are espoused in the literature, the concept is not ubiquitous, nor is it well understood. The purpose of this Joint Applied Project is to evaluate current Department of Defense (DoD) procedures for the use of Alpha contracting. Specifically, we plan to explore Alpha contracting to define what constitutes successful/unsuccessful Alpha contracting, as well as the contributing factors to both outcomes. Additionally, we will identify antecedents for and consequences of use, and variations of the processes employed. This research will identify the utility of Alpha contracting, and explain its narrow usage to date. Using a case study methodology, we will interview experienced Alpha contracting teams, to include contracting officers, DCAA, DCMA, end users/customers, program managers and acquisition directors to better understand the Alpha contracting phenomenon. We will use interview results and research to develop recommendations to address the factors that lead to successful Alpha contracting, as well as the barriers that arise once used.

Introduction Previous studies indicate that overexpression of the membrane-associated mucin MUC4 is potently anti-adhesive to cultured tumor cells, and suppresses cellular apoptotic response to a variety of insults. Such observations raise the possibility that MUC4 expression could contribute to tumor progression or metastasis, but the potential involvement of MUC4 in breast cancer has not been rigorously assessed. The present study aimed to investigate the expression of the membrane mucin MUC4 in normal breast tissue, primary breast tumors and lymph node metastases, and to evaluate the role of MUC4 in promoting the malignant properties of breast tumor cells. Methods MUC4 expression levels in patient-matched normal and tumor breast tissue was initially examined by immunoblotting lysates of fresh frozen tissue samples with a highly specific preparation of anti-MUC4 monoclonal antibody 1G8. Immunohistochemical analysis was then carried out using tissue microarrays encompassing patient-matched normal breast tissue and primary tumors, and patient-matched lymph node metastases and primary tumors. Finally, shRNA-mediated knockdown was employed to assess the contribution of MUC4 to the cellular growth and malignancy properties of JIMT-1 breast cancer cells. Results Immunoblotting and immunohistochemistry revealed that MUC4 levels are suppressed in the majority (58%, p < 0.001) of primary tumors relative to patient-matched normal tissue. On the other hand, lymph node metastatic lesions from 37% (p < 0.05) of patients expressed higher MUC4 protein levels than patient-matched primary tumors. MUC4-positive tumor emboli were often found in lymphovascular spaces of lymph node metastatic lesions. shRNA-mediated MUC4 knockdown compromised the migration, proliferation and anoikis resistance of JIMT-1 cells, strongly suggesting that MUC4 expression actively contributes to cellular properties associated with breast tumor metastasis. Conclusions Our observations suggest that after an initial loss of MUC4 levels during the transition of normal breast tissue to primary tumor, the re-establishment of elevated MUC4 levels confers an advantage to metastasizing breast tumor cells by promoting the acquisition of cellular properties associated with malignancy.

summary Acacia ampliceps B. R. Maslin, A. auriculiformis A. Cunn. ex Benth. and A. mangium Willd. differ in their salt tolerance. Four-month-old seedlings were treated with 100 (S1), 200 (S2) and 400 (S3) mol m−3 NaCl in sand culture. Two months prior to NaCl application the seedlings had been pretreated with either 1 mol m−3 N (low N: LN) or 5 mol m−3 N (high N:HN) as ammonium nitrate. LN seedlings were inoculated with a suspension of Rhizobium. HN plants were considerably larger than inoculated plants at each NaCl concentration. Survival, damage symptoms and relative growth reduction under NaCl were generally similar for both N treatments. There was also no effect of N level on shoot water relations and stomatal conductance of youngest expanded phyllodes. However, at S1 and S2, HN plants had significantly lower concentrations of shoot Na+ and Cl− concentrations than LN plants. There were differences in nodule number and weight per plant between species receiving the LN treatment. Nodule dry weight and nitrogenase (acetylene reduction) activity was more sensitive than plant dry weight to NaCl imposition. Ranking of species for salt tolerance, based on relative decline in dry weight of shoot, whole plant and nodules under NaCl addition, was in the order A. ampliceps > A. aurtculiformsis > A. mangium. The greater salt tolerance of A. ampliceps was associated with relatively low shoot Na+ and Cl− concentrations (dry weight basis) and high phyllode succulence.

Mucins are large, heavily O-glycosylated proteins expressed by epithelial tissues. The canonical function of membrane mucins is to provide protection to vulnerable epithelia by forming a steric barrier against assault, and by contributing to the formation of protective extracellular mucin gels. The aberrant overexpression of mucins is thought to contribute to tumor progression by allowing tumor cells to evade immune recognition, and by aiding in the breakdown of cell-cell and cell-matrix contacts to facilitate migration and metastasis. Recent evidence suggests that we should now modify our thinking about mucin function by considering their roles in signaling pathways leading to cellular growth control. Here we review the markedly divergent mechanisms by which membrane mucins, specifically MUC1 and MUC4, influence pathways contributing to cellular proliferation and survival. The cytoplasmic domain of MUC1 serves as a scaffold for the assembly of a variety of signaling proteins, while MUC4 influences the trafficking and localization of growth factor receptors, and hence their responses to external stimuli. We also discuss how tumor cells exploit these mechanisms to promote their own growth and metastasis.

A real-time PCR assay for the detection of four Leishmania complexes (L. Viannia, L. mexicana, L. donovani/infantum, and L. major) was developed and evaluated. The assay was developed to detect the glucosephosphate isomerase gene and capitalizes on DNA sequence variability within that gene for Leishmania complex identification. Primer/probe sets were created and tested against a panel of 21 known negative controls and on DNA extracted from cultured promastigotes or from tissue biopsies from patients with cutaneous leishmaniasis. The assay was highly specific, as no amplification products were detected in the negative control samples while simultaneously retaining a high degree of complex-specific diagnostic accuracy for cultured organisms and patient clinical samples. Real-time PCR offers rapid (within hours) identification of Leishmania to the complex level and provides a useful molecular tool to assist both epidemiologists and clinicians.

A long-term goal of Arabidopsis research is to define the minimal gene set needed to produce a viable plant with a normal phenotype under diverse conditions. This will require both forward and reverse genetics along with novel strategies to characterize multigene families and redundant biochemical pathways. Here we describe an initial dataset of 250 EMB genes required for normal embryo development in Arabidopsis. This represents the first large-scale dataset of essential genes in a flowering plant. When compared with 550 genes with other knockout phenotypes, EMB genes are enriched for basal cellular functions, deficient in transcription factors and signaling components, have fewer paralogs, and are more likely to have counterparts among essential genes of yeast (Saccharomyces cerevisiae) and worm (Caenorhabditis elegans). EMB genes also represent a valuable source of plant-specific proteins with unknown functions required for growth and development. Analyzing such unknowns is a central objective of genomics efforts worldwide. We focus here on 34 confirmed EMB genes with unknown functions, demonstrate that expression of these genes is not embryo-specific, validate a strategy for identifying interacting proteins through complementation with epitope-tagged proteins, and discuss the value of EMB genes in identifying novel proteins associated with important plant processes. Based on sequence comparison with essential genes in other model eukaryotes, we identify 244 candidate EMB genes without paralogs that represent promising targets for reverse genetics. These candidates should facilitate the recovery of additional genes required for seed development.