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Selected AbstractsOverexpression of CD49f in precursor B-cell acute lymphoblastic leukemia: Potential usefulness in minimal residual disease detectionCYTOMETRY, Issue 2 2009Joseph A. DiGiuseppe Abstract Background: The persistence of minimal residual disease (MRD) following therapy is an established prognostic factor in precursor B-cell acute lymphoblastic leukemia (pB-ALL). Detection of MRD in pB-ALL by flow cytometric immunophenotyping requires demonstration of abnormal antigen expression in leukemic B-cell precursors relative to that of normal B-cell precursors. The gene encoding CD49f (integrin ,-6) is one of several whose overexpression in pB-ALL at diagnosis has been associated with the subsequent detection of MRD. However, whether CD49f might be a useful reagent in the immunophenotypic detection of MRD in pB-ALL has not been evaluated. Methods: We evaluated CD49f expression by 4-color flow cytometry in normal B-cell precursors, and in a series of cases of pB-ALL, both at diagnosis and at intervals following the initiation of therapy. Results: In 10 control marrow samples, CD49f was undetectable or extremely dim in all but a minor subset of normal CD19+ B-lineage cells, whereas in 11 of 15 cases (73%) of pB-ALL, CD49f was moderate or bright at diagnosis, and persisted or became brighter after initiation of therapy. MRD detected using CD49f corresponded precisely with that obtained using a standard panel of antibodies, and permitted the detection of leukemic populations comprising as little as 0.02% of cells. Of the four pB-ALL cases in which CD49f was undetectable or dim at diagnosis, MRD was detected in two; in one of these, CD49f expression was substantially increased in the leukemic cells that persisted following initiation of therapy. Conclusions: CD49f is commonly overexpressed in p-B-ALL, and represents a potentially useful marker for the immunophenotypic detection of MRD. © 2008 Clinical Cytometry Society How to cite this article: DiGiuseppe JA, Fuller SG, Borowitz MJ. Overexpression of CD49f in precursor B-cell acute lymphoblastic leukemia: potential usefulness in minimal residual disease detection. Cytometry Part B 2008. [source] Sustained attention as a potential endophenotype for bipolar disorderACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010I. Ancín Ancín I, Santos JL, Teijeira C, Sánchez-Morla EM, Bescós MJ, Argudo I, Torrijos S, Vázquez-Álvarez B, De La Vega I, López-Ibor JJ, Barabash A, Cabranes-Díaz JA. Sustained attention as a potential endophenotype for bipolar disorder. Objective:, Nowadays, it is accepted that to identify the biological basis of psychiatric illnesses it would be useful to deconstruct them into the most basic manifestations, such as cognitive deficits. The aim of this study was to set attention deficit as a stable vulnerability marker of bipolar disorder. Method:, Sustained attention was evaluated by the Continuous Performance Test (DS-CPT) in 143 euthymic bipolar patients and 105 controls. To estimate the influence of clinical profile in attention, patients completed a semi-structured interview. Results:, Bipolar patients showed a deficit in attention during euthymic periods. This disturbance correlated with years of evolution, age of onset and age of first hospitalisation; and was not influenced by other clinical data. Conclusion:, Sustained attention may be considered as an endophenotype of the illness. [source] Treatment of unipolar psychotic depression: a randomized, double-blind study comparing imipramine, venlafaxine, and venlafaxine plus quetiapineACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010J. Wijkstra Wijkstra J, Burger H, van den Broek WW, Birkenhäger TK, Janzing JGE, Boks MPM, Bruijn JA, van der Loos MLM, Breteler LMT, Ramaekers GMGI, Verkes RJ, Nolen WA. Treatment of unipolar psychotic depression: a randomized, double-blind study comparing imipramine, venlafaxine, and venlafaxine plus quetiapine. Objective:, It remains unclear whether unipolar psychotic depression should be treated with an antidepressant and an antipsychotic or with an antidepressant alone. Method:, In a multi-center RCT, 122 patients (18,65 years) with DSM-IV-TR psychotic major depression and HAM-D-17 , 18 were randomized to 7 weeks imipramine (plasma-levels 200,300 ,g/l), venlafaxine (375 mg/day) or venlafaxine,quetiapine (375 mg/day, 600 mg/day). Primary outcome was response on HAM-D-17. Secondary outcomes were response on CGI and remission (HAM-D-17). Results:, Venlafaxine,quetiapine was more effective than venlafaxine with no significant differences between venlafaxine,quetiapine and imipramine, or between imipramine and venlafaxine. Secondary outcomes followed the same pattern. Conclusion:, That unipolar psychotic depression should be treated with a combination of an antidepressant and an antipsychotic and not with an antidepressant alone, can be considered evidence based with regard to venlafaxine,quetiapine vs. venlafaxine monotherapy. Whether this is also the case for imipramine monotherapy is likely, but cannot be concluded from the data. [source] Plant oxylipins: COI1/JAZs/MYC2 as the core jasmonic acid-signalling moduleFEBS JOURNAL, Issue 17 2009Andrea Chini Jasmonic acid (JA) and its derivates, collectively known as jasmonates (JAs), are essential signalling molecules that coordinate the plant response to biotic and abiotic challenges, in addition to several developmental processes. The COI1 F-box and additional SCF modulators have long been known to have a crucial role in the JA-signalling pathway. Downstream JA-dependent transcriptional re-programming is regulated by a cascade of transcription factors and MYC2 plays a major role. Recently, JAZ family proteins have been identified as COI1 targets and repressors of MYC2, defining the ,missing link' in JA signalling. JA,Ile has been proposed to be the active form of the hormone, and COI1 is an essential component of the receptor complex. These recent discoveries have defined the core JA-signalling pathway as the module COI1/JAZs/MYC2. [source] Apical transportation created using three different patency instrumentsINTERNATIONAL ENDODONTIC JOURNAL, Issue 7 2010J. A. Gonzalez Sanchez Gonzalez Sanchez JA, Duran-Sindreu F, Albuquerque Matos M, Garcia Carabaño T, Mercade Bellido M, Morello Castro S, Roig Cayón M. Apical transportation created using three different patency instruments. International Endodontic Journal 43, 560,564, 2010. Abstract Aim, To evaluate root canal transportation at the major foramen through the use of stainless steel size 08 K-Flex files, size 10 reamers, and XF finger spreaders when used as patency instruments. Methodology, One hundred and two mesiobuccal canals of maxillary and mandibular first molars were randomly divided into three groups (34 canals each). Size 08 stainless steel K-Flex files, size 10 stainless steel reamers and stainless steel XF finger spreaders were used as patency instruments in groups A, B and C respectively. The major foramen was photographed before and after instrumentation. The images were superimposed and then evaluated using Photoshop® to determine the frequency of apical transportation. The statistic analysis was performed using ,2test. Results, Transportation was detected in 22% of the specimens; 9% in group A, 12% in group B and 44% in group C. Significant differences were observed between groups A and C (P = 0.0025) and between groups B and C (P = 0.0069), but not between groups A and B (P = 1.00). Conclusions, No transportation was found in the majority of the samples when size 08 K-Flex files and size 10 stainless steel reamers were used. The XF finger spreaders, when used to maintain apical patency, caused the greatest transportation of the major foramen. [source] Response surface methodology to optimize the nutritional parameters for enhanced production of jasmonic acid by Lasiodiplodia theobromaeJOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2008P.C. Dhandhukia Abstract Aims:, To find out the cumulative effect of the nutritional parameters and to enhance the production of jasmonic acid (JA) in static fermentation by Lasiodiplodia theobromae using response surface methodology (RSM). Method and Results:, Malt extract, sucrose, NaNO3 and MgSO4.7H2O were analysed by a 30-trial central composite design using RSM for optimizing their concentrations in the medium and the effect of their mutual interaction on JA production. Sucrose and NaNO3 were found highly significant in influencing the JA production. Malt extract and MgSO4.7H2O showed an effect on the JA production in interaction with other variables. When the optimum values of the parameters obtained through RSM (19·95 g l,1 malt extract, 50 g l,1 sucrose, 7·5 g l,1 NaNO3 and 3·51 g l,1 MgSO4.7H2O) were applied, 32% increase in JA production (299 mg l,1) was observed in comparison with 225 mg l,1 of JA produced with same media components not analysed by RSM and subsequently validated the statistical model. Conclusions:, Increase in JA production was achieved by optimizing the nutritional parameters. Significance and Impact of the Study:, This is the first report of using RSM for optimizing a medium for JA production. It resulted in an increase in JA production without augmentation of costly additives. [source] Association of salivary lysozyme and C-reactive protein with metabolic syndromeJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2010Markku Qvarnstrom Qvarnstrom M, Janket S-J, Jones JA, Jethwani K, Nuutinen P, Garcia RI, Baird AE, Van Dyke TE and Meurman JH. Association of salivary lysozyme and C-reactive protein with metabolic syndrome. J Clin Periodontol 2010; 37: 805,811. doi: 10.1111/j.1600-051X.2010.01605.x. Abstract Introduction: Salivary lysozyme (SLZ) is a proteolytic enzyme secreted by oral leucocytes and contains a domain that has an affinity to advanced glycation end products (AGE). Thus, we hypothesized that SLZ would be associated with metabolic syndrome (metS), a pro-inflammatory state. Methods: Utilizing cross-sectional data from 250 coronary artery disease (CAD) and 250 non-CAD patients, the association of SLZ with metS was tested by logistic regression analyses controlling for age, sex, smoking, total cholesterol and C-reactive protein (CRP) levels. The analyses were stratified by CAD status to control for the possible effects of CAD. Results: MetS was found in 122 persons. The adjusted odds ratio (OR) for metS associated with the highest quartile of SLZ was 1.95 with 95% confidence interval (CI) 1.20,3.12, p -value=0.007, compared with the lower three quartiles combined. Among the 40 subjects with metS but without CAD, the OR was 1.63 (CI: 0.64,4.15, p=0.31), whereas in the CAD group, SLZ was significantly associated with metS [OR=1.96 (1.09,3.52), p=0.02]. In both subgroups, CRP was not significantly associated with metS. Conclusion: SLZ was significantly associated with metS (OR=1.95) independent of CRP level. Future longitudinal research is warranted. [source] Value of p63 and podoplanin (D2-40) immunoreactivity in the distinction between primary cutaneous tumors and adenocarcinomas metastatic to the skin: a clinicopathologic and immunohistochemical study of 79 casesJOURNAL OF CUTANEOUS PATHOLOGY, Issue 4 2010Jose A. Plaza The distinction of metastatic carcinomas to the skin from poorly differentiated primary cutaneous carcinomas and sometimes primary benign adnexal tumors can pose a significant diagnostic challenge. The purpose of this study was to evaluate the role of p63 and podoplanin (D2-40) immunoreactivity for separating primary skin tumors vs. cutaneous metastases of carcinomas from internal organs. Thirty seven primary tumors and 42 cutaneous metastatic adenocarcinomas were evaluated. The 37 primary cutaneous tumors included 14 cases of benign adnexal tumors, 9 malignant skin adnexal neoplasms, and 14 primary squamous and basal cell carcinomas. The 42 metastatic adenocarcinomas all corresponded to metastases from patients with a well-documented history of a primary tumor at another location. We found variable positivity with podoplanin in all primary cutaneous neoplasms including spiradenoma (6/6), hidradenoma (2/4), cylindroma (3/3), desmoplastic trichilemmoma (1/1), poorly differentiated squamous cell carcinoma (4/4), sebaceous carcinoma (1/1), basal cell carcinoma (4/10), trichilemmal carcinoma (2/2), eccrine carcinoma (3/3), microcystic adnexal carcinoma (1/1), adnexal carcinoma NOS (1/1), and porocarcinoma (1/1). In contrast, all metastatic carcinomas were negative (0/42) for podoplanin. In regards to p63, all cases of primary cutaneous tumors were positive for p63 (37/37); in contrast, all cutaneous metastatic carcinomas were negative (0/42). Sensitivity, specificity, and positive and negative predictive values of podoplanin and p63 immunoreactivity to separate primary skin neoplasms from metastatic carcinomas were 78.4, 100.0, 100.0 and 84.0% for podoplanin, respectively, and 100.0, 100.0, 100.0 and 100.0% for p63, respectively. The differences in p63 and podoplanin immunohistochemical expression between primary skin tumors and metastatic carcinomas to the skin were statistically significant (p < 0, 0001). The results of our study suggest that the combined expression of p63 and podoplanin are a useful adjunct for the diagnosis of skin tumors in the clinical setting of a questionable metastasis and may be relatively specific for distinguishing primary skin tumors from metastatic carcinomas to the skin. Plaza JA, Ortega PF, Stockman DL, Suster S. Value of p63 and podoplanin (D2-40) immunoreactivity in the distinction between primary cutaneous tumors and adenocarcinomas metastatic to the skin: a clinicopathologic and immunohistochemical study of 79 cases. [source] Gibberellin and Jasmonate Crosstalk during Stamen DevelopmentJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 12 2009Jinrong Peng Abstract Gibberellin (GA) and jasmonate (JA) are two types of phytohormones that play important roles during stamen development. For example, Arabidopsis plants deficient in either of GA or JA develop short stamens. An apparent question to ask is whether GA action and JA action during stamen filament development are independent of each other or are in a hierarchy. Recent studies showed that GA modulates the expression of genes essential for JA biosynthesis to promote JA production and high levels of JA will induce the expression of three MYB genes MYB21, MYB24 and MYB57. These three MYB genes are crucial factors for the normal development of stamen filament in Arabidopsis. [source] An Integrative Analysis of the Effects of Auxin on Jasmonic Acid Biosynthesis in Arabidopsis thalianaJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 1 2006Jun Liu Abstract Auxin and jasmonic acid (JA) are two plant phytohormones that both participate in the regulation of many developmental processes. Jasmonic acid also plays important roles in plant stress response reactions. Although extensive investigations have been undertaken to study the biological functions of auxin and JA, little attention has been paid to the cross-talk between their regulated pathways. In the few available reports examining the effects of auxin on the expression of JA or JA-responsive genes, both synergetic and antagonistic results have been found. To further investigate the relationship between auxin and JA, we adopted an integrative method that combines microarray expression data with pathway information to study the behavior of the JA biosynthesis pathway under auxin treatment. Our results showed an overall down regulation of genes involved in JA biosynthesis, providing the first report of a relationship between auxin and the JA synthesis pathway in Arabidopsis seedlings. (Managing editor: Ya-Qin Han) [source] Community-acquired febrile urinary tract infection in diabetics could deserve a different management: a case,control studyJOURNAL OF INTERNAL MEDICINE, Issue 3 2003J. P. Horcajada Abstract., Horcajada JP, Moreno I, Velasco M, Martínez JA, Moreno-Martínez A, Barranco M, Vila J, Mensa J (Hospital Clínic Universitari-IDIBAPS, Barcelona, Spain) Community-acquired febrile urinary tract infection in diabetics could deserve a different management: a case,control study. J Intern Med 2003; 254: 280,286. Objective., To investigate if there are relevant differences in clinical, microbiological and outcome characteristics of community-acquired febrile urinary tract infection (UTI) between diabetic and nondiabetic patients. Design., A prospectively matched case,control study. Setting., An 800-bed tertiary care university-affiliated hospital. Subjects., A total of 108 patients (54 diabetic and 54 nondiabetic patients matched by age and gender) admitted between January 1996 and September 1999 with febrile UTI. Methods., Clinical, analytical, microbiological and outcome variables were analysed by means of McNemar test (categorical) or Wilcoxon matched pairs signed rank test (continuous). Results., Mean age (SD) in both groups was 67.9 (14.4) years. In comparison with controls, diabetic patients were more likely to have fever without localizing symptoms (27% vs. 9%, P , 0.0001), diminished consciousness level at admission (25% vs. 10%, P = 0.03), aetiological microorganism different from Escherichia coli (17% vs. 0, P = 0.0004), and quinolone-resistant bacteria (17% vs. 3.7%, P = 0.07). Duration of fever after the onset of treatment was 1.75 (1) days in diabetics and 1.5 (1.1) days in nondiabetics (P = 0.17). However, diabetic patients had a longer hospitalization [5.2 (3.3) days] than nondiabetics [3.9 (2.6) days, P = 0.006]. Conclusions., In diabetic patients, febrile UTIs have clinical and microbiological peculiarities that may have diagnostic and therapeutic implications. [source] Work-related stress, inability to relax after work and risk of adult asthma: a population-based cohort studyALLERGY, Issue 10 2010A. Loerbroks To cite this article: Loerbroks A, Gadinger MC, Bosch JA, Stürmer T, Amelang M. Work-related stress, inability to relax after work and risk of adult asthma: a population-based cohort study. Allergy 2010; 65: 1298,1305. Abstract Background:, There is an extensive literature linking stressful work conditions to adverse health outcomes. Notwithstanding, the relationship with asthma has not been examined, although various other measures of psychological stress have been associated with asthma. Therefore, we aimed to investigate the relation between work stress and asthma prevalence and incidence. Methods:, We used data from a population-based cohort study (n = 5114 at baseline in 1992,1995 and n = 4010 at follow-up in 2002/2003). Asthma was measured by self-reports. Two scales that assessed psychologically adverse work conditions were extracted from a list of work-condition items by factor analysis (these scales were termed ,work stress' and ,inability to relax after work'). For each scale, the derived score was employed both as continuous z -score and as categorized variable in analyses. Associations with asthma were estimated by prevalence ratios (PRs) and risk ratios (RRs) using Poisson regression with a log-link function adjusting for demographics, health-related lifestyles, body mass index and family history of asthma. Analyses were restricted to those in employment (n = 3341). Results:, Work stress and inability to relax z -scores were positively associated with asthma prevalence (PR = 1.15, 95%CI = 0.97, 1.36 and PR = 1.43, 95%CI = 1.12, 1.83, respectively). Prospective analyses using z -scores showed that for each 1 standard deviation increase in work stress and inability to relax, the risk of asthma increased by approximately 40% (RR for work stress = 1.46, 95%CI = 1.06, 2.00; RR for inability to relax = 1.39, 95%CI = 1.01, 1.91). Similar patterns of associations were observed in analyses of categorized exposures. Conclusions:, This is the first study to show a cross-sectional and longitudinal association of work stress with asthma. [source] Validation of a questionnaire (CARAT10) to assess rhinitis and asthma in patients with asthmaALLERGY, Issue 8 2010J. A. Fonseca To cite this article: Fonseca JA, Nogueira-Silva L, Morais-Almeida M, Azevedo L, Sa-Sousa A, Branco-Ferreira M, Fernandes L, Bousquet J. Validation of a questionnaire (CARAT10) to assess rhinitis and asthma in patients with asthma. Allergy 2010; 65: 1042,1048. Abstract Background and aim:, The Control of Allergic Rhinitis and Asthma Test (CARAT) was developed to be used in the concurrent management of these diseases, as recommended by the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines. However, it was necessary to statistically identify and remove redundant questions and to evaluate the new version's factor structure, internal consistency and concurrent validity. Methods:, In this cross-sectional study 193 adults with allergic rhinitis and asthma from 15 outpatient clinics in Portugal were included. The CARAT questionnaire was reduced using descriptive analysis, exploratory factor analysis and internal consistency. Spearman's correlations were used to compare the CARAT scores with a medical evaluation and other measures of control, including the Asthma Control Questionnaire and symptoms' visual analogue scales. The performance against physician rating of control was summarized using the area under the curve (AUC) from receiver operating characteristic analysis. In addition, CARAT was compared with the physician's decision to reduce, maintain or increase treatment. Results:, The reduced version has 10 questions and 2 factors (CARAT10). The Cronbach's alpha was 0.85. All correlation coefficients of CARAT10 and factors with the different measures of control met the a priori predictions, ranging from 0.58 to 0.79. The AUC was 0.82. For the physician's decision groups of reduce, maintain or increase treatment, the mean (IC95%) scores of CARAT10 were 24 (21.4;26.6), 21 (19.4;21.9) and 15 (13.6;16.5), respectively. Conclusion:, CARAT10 has high internal consistency and good concurrent validity, making it useful to compare groups in clinical studies. [source] Anaphylaxis to patent blue V: a case series and proposed diagnostic protocolALLERGY, Issue 3 2010R. A. Haque To cite this article: Haque RA, Wagner A, Whisken JA, Nasser SM, Ewan PW. Anaphylaxis to patent blue V: a case series and proposed diagnostic protocol. Allergy 2010; 65: 396,400. Abstract Patent blue V is widely used in the identification of sentinel lymph nodes in patients with breast cancer and other malignancies. Individual case reports of allergy to patent blue V have been described in the medical literature since the 1960s. However, there is little data on clinical features and little experience of which allergy tests are appropriate or useful. We gathered all cases of patent blue V allergy that had been seen and diagnosed in the Department of Allergy, Addenbrooke's Hospital over a 3-year period. We collected clinical details of each case including skin test results. For comparison we recruited 12 healthy control subjects who then underwent skin testing to patent blue V. Six cases of patent blue V allergy were identified, all occurring during sentinel lymph node identification for breast carcinoma. All 6 had positive skin prick tests to neat patent blue V (25 mg/ml). Skin prick testing with a 1 : 10 dilution (2.5 mg/ml) produced positive results in 3 of 4 patients tested, and intradermal testing at a 1 : 100 dilution was (0.25 mg/ml) was positive in all patients tested. Of 12 control subjects, 11 had negative skin prick tests to both neat and 1 : 10 patent blue V with one subject showing a positive reaction to the higher concentration only. On the basis of our experience of patent blue V allergy, we propose a diagnostic protocol that can be safely and reliably utilised in centres equipped for allergy testing. [source] The importance of environment on respiratory genotype/phenotype relationships in the InuitALLERGY, Issue 2 2010P. V. Candelaria To cite this article: Candelaria PV, Backer V, Khoo S-K, Bizzintino JA, Hayden CM, Baynam G, Laing IA, Zhang G, Porsbjerg C, Goldblatt J, LeSouëf PN, The Greenlandic Study Population Group. The importance of environment on respiratory genotype/phenotype relationships in the Inuit. Allergy 2010; 65: 229,237. Abstract Background:, Genetic and environmental influences and their interactions are central to asthma pathogenesis. This study aimed to investigate the effects of different macro-environments on asthma genotype,phenotype associations in two geographically separated populations with common ancestry. Methods:, To accomplish this, two unselected populations of Inuit were recruited, one living in Greenland (n = 618) and the other in Denmark (n = 739). Subjects were genotyped for CD14 C-159T, SCGB1A1 A38G, ADRB2 Arg16Gly and Gln27Glu. The resulting genetic data were analysed for relationships with asthma-related parameters including lung function, ever asthma, atopy, rhinitis and dermatitis. Results:, The results showed contrasting magnitude and direction of genetic associations between the two geographically separate Inuit populations. In Greenland, the ADRB2 16Arg allele was associated with male-specific lower lung function, but in Denmark the same allele was associated with male-specific higher lung function. This allele was also associated with higher incidence of ever asthma in Denmark but not in Greenland. The SCGB1A1 38A allele was associated with lower rhinitis prevalence in Greenland but not in Denmark. Conclusions:, These associations suggest that environment interacts with candidate asthma genes to modulate asthma pathogenesis in the Inuit. [source] NPR1 and EDS11 contribute to host resistance against Fusarium culmorum in Arabidopsis buds and flowersMOLECULAR PLANT PATHOLOGY, Issue 5 2008ALAYNE CUZICK SUMMARY The cereal ear blight fungal pathogen Fusarium culmorum can infect Arabidopsis floral tissue, causing disease symptoms and mycotoxin production. Here we assessed the effect of seven mutants and one transgenic overexpression line, residing in either the salicylic acid (SA), jasmonic acid (JA) or ethylene (ET) defence signalling pathways, on the outcome of the Fusarium,Arabidopsis floral interaction. The bacterial susceptiblity mutant eds11 was also assessed. Flowering plants were spray inoculated with F. culmorum conidia to determine the host responses to initial infection and subsequent colonization. Enhanced susceptibility and higher concentrations of deoxynivalenol mycotoxin were observed in buds and flowers of the npr1 and eds11 mutants than in the wild-type Col-0 plants. An effect of the other two defence signalling pathways on disease was either absent (ET/JA combined), absent/minimal (ET) or inconclusive (JA). Overall, this study highlights a role for NPR1 and EDS11 in basal defence against F. culmorum in some floral organs. This is the first time that any of these well-characterized defence signalling mutations have been evaluated for a role in floral defence in any plant species. [source] Layers of defense responses to Leptosphaeria maculans below the RLM1 - and camalexin-dependent resistancesNEW PHYTOLOGIST, Issue 2 2009Mattias Persson Summary ,,Plants have evolved different defense components to counteract pathogen attacks. The resistance locus resistance to Leptosphaeria maculans 1 (RLM1) is a key factor for Arabidopsis thaliana resistance to L. maculans. The present work aimed to reveal downstream defense responses regulated by RLM1. ,,Quantitative assessment of fungal colonization in the host was carried out using quantitative polymerase chain reaction (qPCR) and GUS expression analyses, to further characterize RLM1 resistance and the role of salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) in disease development. Additional assessments of A. thaliana mutants were performed to expand our understanding of this pathosystem. ,,Resistance responses such as lignification and the formation of vascular plugs were found to occur in an RLM1 -dependent manner, in contrast to the RLM1 -independent increase in reactive oxygen species at the stomata and hydathodes. Analyses of mutants defective in hormone signaling in the camalexin-free rlm1Lerpad3 background revealed a significant influence of JA and ET on symptom development and pathogen colonization. ,,The overall results indicate that the defense responses of primary importance induced by RLM1 are all associated with physical barriers, and that responses of secondary importance involve complex cross-talk among SA, JA and ET. Our observations further suggest that ET positively affects fungal colonization. [source] Gibberellins, jasmonate and abscisic acid modulate the sucrose-induced expression of anthocyanin biosynthetic genes in ArabidopsisNEW PHYTOLOGIST, Issue 4 2008Elena Loreti Summary ,,Anthocyanins are secondary metabolites, which play an important role in the physiology of plants. Both sucrose and hormones regulate anthocyanin synthesis. Here, the interplay between sucrose and plant hormones was investigated in the expression of sucrose-regulated genes coding for anthocyanin biosynthetic enzymes in Arabidopsis seedlings. ,,The expression pattern of 14 genes involved in the anthocyanin biosynthetic pathway, including two transcription factors (PAP1, PAP2), was analysed by real-time reverse transcriptase polymerase chain reaction (RT-PCR) in Arabidopsis seedlings treated with sucrose and plant hormones. ,,Sucrose-induction of the anthocyanin synthesis pathway was repressed by the addition of gibberellic acid (GA) whereas jasmonate (JA) and abscisic acid (ABA) had a synergic effect with sucrose. The gai mutant was less sensitive to GA-dependent repression of dihydroflavonol reductase. This would seem to prove that GAI signalling is involved in the crosstalk between sucrose and GA in wild-type Arabidopsis seedlings. Conversely, the inductive effect of sucrose was not strictly ABA mediated. Sucrose induction of anthocyanin genes required the COI1 gene, but not JAR1, which suggests a possible convergence of the jasmonate- and sucrose-signalling pathways. ,,The results suggest the existence of a crosstalk between the sucrose and hormone signalling pathways in the regulation of the anthocyanin biosynthetic pathway. [source] Perinatal nutrition and immunity to infectionPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 4p1 2010Kelsey D. J. Jones Jones KDJ, Berkley JA, Warner JO. Perinatal nutrition and immunity to infection. Pediatr Allergy Immunol 2010: 21: 564,576. © 2010 John Wiley & Sons A/S Epidemiological data provide strong evidence for a relationship between undernutrition and life-threatening infection in infants and children. However, the mechanisms that underlie this relationship are poorly understood. Through foetal life, infancy and childhood, the immune system undergoes a process of functional maturation. The adequacy of this process is dependent on environmental factors, and there is accumulating evidence of the impact of pre- and post-natal nutrition in this regard. This review outlines the impact of nutrition during foetal and infant development on the capacity to mount immune responses to infection. It provides an overview of the epidemiologic evidence for such a role and discusses the possible mechanisms involved. [source] The changing face of post-transplant lymphoproliferative disease in the era of molecular EBV monitoringPEDIATRIC TRANSPLANTATION, Issue 4 2010Nanda Kerkar Kerkar N, Morotti RA, Madan RP, Shneider B, Herold BC, Dugan C, Miloh T, Karabicak I, Strauchen JA, Emre S. The changing face of post-transplant lymphoproliferative disease in the era of molecular EBV monitoring. Pediatr Transplantation 2010: 14:504,511. © 2010 John Wiley & Sons A/S. Abstract:, Pediatric PTLD is often associated with primary EBV infection and immunosuppression. The aim was to retrospectively review the spectrum of histologically documented PTLD for two time intervals differentiated by changes in use of molecular EBV monitoring. Eleven of 146 patients (7.5%) in 2001,2005 (Era A) and 10 of 92 (10.9%) in 1993,1997 (Era B) were diagnosed with PTLD. The median age at liver transplantation (0.8 and 0.9 yr, respectively) and the median duration between liver transplant and diagnosis of PTLD (0.6 and 0.7 yr, respectively) were similar in both eras. However, patients in Era A presented with significantly less advanced histological disease compared to patients in Era B (p = 0.03). Specifically, nine patients (82%) in Era A had Pl hyperplasia/polymorphic PTLD, whereas in Era B, six had advanced histological disease (five monomorphic and one unclassified). Three transplant recipients in Era B died secondary to PTLD, whereas there were no PTLD-related deaths in Era A (p = 0.03). Heightened awareness of risk for PTLD, alterations in baseline immunosuppression regimens, implementation of molecular EBV monitoring, pre-emptive reduction in immunosuppression and improved therapeutic options may have all contributed to a milder PTLD phenotype and improved clinical outcomes. [source] Long-term outcome of intensive initial immunosuppression protocol in pediatric deceased donor renal transplantationPEDIATRIC TRANSPLANTATION, Issue 1 2010Oyedolamu K. Olaitan Olaitan OK, Zimmermann JA, Shields WP, Rodriguez-Navas G, Awan A, Mohan P, Little DM, Hickey DP. Long-term outcome of intensive initial immunosuppression protocol in pediatric deceased donor renal transplantation. Pediatr Transplantation 2010: 14: 87,92. © 2009 John Wiley & Sons A/S. Abstract:, To report the long-term outcome of deceased donor kidney transplantation in children with emphasis on the use of an intensive initial immunosuppression protocol using R-ATG as antibody induction. Between January 1991 and December 1997, 82 deceased donor kidney transplantations were performed in 75 pediatric recipients. Mean recipient age at transplantation was 12.9 yr and the mean follow-up period was 12.6 yr. All patients received quadruple immunosuppression with steroid, cyclosporine, azathioprine, and antibody induction using R-ATG-Fresenius®. Actual one, five, and 10 yr patient survival rates were 99%, 97%, and 94%, respectively; only one patient (1.2%) developed PTLD. Actual one, five, and 10 yr overall graft survival rates were 84%, 71%, and 50%, respectively; there were five cases (6%) of graft thrombosis and the actual immunological graft survival rates were 91%, 78%, and 63% at one, five, and 10 yr, respectively. The use of an intensive initial immunosuppression protocol with R-ATG as antibody induction is safe and effective in pediatric recipients of deceased donor kidneys with excellent immunological graft survival without an increase in PTLD or other neoplasms over a minimum 10-yr follow up. [source] Epigenetic chromatin modifiers in barley: I. Cloning, mapping and expression analysis of the plant specific HD2 family of histone deacetylases from barley, during seed development and after hormonal treatmentPHYSIOLOGIA PLANTARUM, Issue 3 2009Kyproula Demetriou Epigenetic phenomena have been associated with modifications of chromatin structure. These are achieved, in part, by histone post-translational modifications including acetylations and deacetylations, the later being catalyzed by histone deacetylaces (HDACs). Eukaryotic HDACs are grouped into three major families, RPD3/HDA1, SIR2 and the plant-specific HD2. HDAC genes have been analyzed from model plants such as Arabidopsis, rice and maize and have been shown to be involved in various cellular processes including seed development, vegetative and reproductive growth and responses to abiotic and biotic stress, but reports on HDACs from other crops are limited. In this work two full-length cDNAs (HvHDAC2-1 and HvHDAC2-2) encoding two members of the plant-specific HD2 family, respectively, were isolated and characterized from barley (Hordeum vulgare), an agronomically important cereal crop. HvHDAC2-1 and HvHDAC2-2 were mapped on barley chromosomes 1H and 3H, respectively, which could prove useful in developing markers for marker-assisted selection in breeding programs. Expression analysis of the barley HD2 genes demonstrated that they are expressed in all tissues and seed developmental stages examined. Significant differences were observed among tissues and seed stages, and between cultivars with varying seed size, suggesting an association of these genes with seed development. Furthermore, the HD2 genes from barley were found to respond to treatments with plant stress-related hormones such as jasmonic acid (JA), abscisic acid (ABA) and salicylic acid (SA) implying an association of these genes with plant resistance to biotic and abiotic stress. The expression pattern of HD2 genes suggests a possible role for these genes in the epigenetic regulation of seed development and stress response. [source] Fine-Tuning Plant Defence Signalling: Salicylate versus JasmonatePLANT BIOLOGY, Issue 1 2006G. J. M. Beckers Abstract: Plant defences against pathogens and herbivorous insects form a comprehensive network of interacting signal transduction pathways. The signalling molecules salicylic acid (SA) and jasmonic acid (JA) play important roles in this network. SA is involved in signalling processes providing systemic acquired resistance (SAR), protecting the plant from further infection after an initial pathogen attack. SAR is long-lasting and provides broad spectrum resistance to biotrophic pathogens that feed on a living host cell. The regulatory protein NPR1 is a central positive regulator of SAR. SA-activated NPR1 localizes to the nucleus where it interacts with TGA transcription factors to induce the expression of a large set of pathogenesis-related proteins that contribute to the enhanced state of resistance. In a distinct signalling process, JA protects the plant from insect infestation and necrotrophic pathogens that kill the host cell before feeding. JA activates the regulatory protein COI1 that is part of the E3 ubiquitin ligase-containing complex SCFCOI1, which is thought to derepress JA-responsive genes involved in plant defence. Both synergistic and antagonistic interactions have been observed between SA- and JA-dependent defences. NPR1 has emerged as a critical modulator of cross-talk between the SA and JA signal and is thought to aid in fine tuning defence responses specific to the encountered attacker. Here we review SA- and JA-dependent signal transduction and summarize our current understanding of the molecular mechanisms of cross-talk between these defences. [source] Functional analysis of rice NPR1 -like genes reveals that OsNPR1/NH1 is the rice orthologue conferring disease resistance with enhanced herbivore susceptibility,PLANT BIOTECHNOLOGY JOURNAL, Issue 2 2007Yuexing Yuan Summary The key regulator of salicylic acid (SA)-mediated resistance, NPR1, is functionally conserved in diverse plant species, including rice (Oryza sativa L.). Investigation in depth is needed to provide an understanding of NPR1 -mediated resistance and a practical strategy for the improvement of disease resistance in the model crop rice. The rice genome contains five NPR1 -like genes. In our study, three rice homologous genes, OsNPR1/NH1, OsNPR2/NH2 and OsNPR3, were found to be induced by rice bacterial blight Xanthomonas oryzae pv. oryzae and rice blast Magnaporthe grisea, and the defence molecules benzothiadiazole, methyl jasmonate and ethylene. We confirmed that OsNPR1 is the rice orthologue by complementing the Arabidopsis npr1 mutant. Over-expression of OsNPR1 conferred disease resistance to bacterial blight, but also enhanced herbivore susceptibility in transgenic plants. The OsNPR1-green fluorescent protein (GFP) fusion protein was localized in the cytoplasm and moved into the nucleus after redox change. Mutations in its conserved cysteine residues led to the constitutive localization of OsNPR1(2CA)-GFP in the nucleus and also abolished herbivore hypersensitivity in transgenic rice. Different subcellular localizations of OsNPR1 antagonistically regulated SA- and jasmonic acid (JA)-responsive genes, but not SA and JA levels, indicating that OsNPR1 might mediate antagonistic cross-talk between the SA- and JA-dependent pathways in rice. This study demonstrates that rice has evolved an SA-mediated systemic acquired resistance similar to that in Arabidopsis, and also provides a practical approach for the improvement of disease resistance without the penalty of decreased herbivore resistance in rice. [source] The Arabidopsis gene SIGMA FACTOR-BINDING PROTEIN 1 plays a role in the salicylate- and jasmonate-mediated defence responsesPLANT CELL & ENVIRONMENT, Issue 5 2010Y.-D. XIE ABSTRACT The chloroplast-localized SIB1 protein was previously identified by its interaction with SIGMA FACTOR 1 (SIG1), a component of the RNA polymerase machinery responsible for transcription of plastid genes. The physiological function of SIB1 is little known. We found that expression of SIB1 is induced by infection with Pseudomonas syringae, suggesting its possible involvement in the defence response. The sib1 loss-of-function mutation compromises induction of some defence-related genes triggered by pathogen infection and the treatments with salicylic acid (SA) and jasmonic acid (JA), two key signalling molecules in the defence response. Conversely, constitutive over-expression of SIB1 causes the plants to hyper-activate defence-related genes following pathogen infection or the SA and JA treatments, leading to enhanced resistance to infection by P. syringae. SIB1 is a member of the large plant-specific VQ motif-containing protein family, and might act as a link to connect defence signalling with chloroplast function. [source] Parasitism by Cuscuta pentagona sequentially induces JA and SA defence pathways in tomatoPLANT CELL & ENVIRONMENT, Issue 2 2010JUSTIN B. RUNYON ABSTRACT While plant responses to herbivores and pathogens are well characterized, responses to attack by other plants remain largely unexplored. We measured phytohormones and C18 fatty acids in tomato attacked by the parasitic plant Cuscuta pentagona, and used transgenic and mutant plants to explore the roles of the defence-related phytohormones salicylic acid (SA) and jasmonic acid (JA). Parasite attachment to 10-day-old tomato plants elicited few biochemical changes, but a second attachment 10 d later elicited a 60-fold increase in JA, a 30-fold increase in SA and a hypersensitive-like response (HLR). Host age also influenced the response: neither Cuscuta seedlings nor established vines elicited a HLR in 10-day-old hosts, but both did in 20-day-old hosts. Parasites grew larger on hosts deficient in SA (NahG) or insensitive to JA [jasmonic acid-insensitive1 (jai1) ], suggesting that both phytohormones mediate effective defences. Moreover, amounts of JA peaked 12 h before SA, indicating that defences may be coordinated via sequential induction of these hormones. Parasitism also induced increases in free linolenic and linoleic acids and abscisic acid. These findings provide the first documentation of plant hormonal signalling induced by a parasitic plant and show that tomato responses to C. pentagona display characteristics similar to both herbivore- and pathogen-induced responses. [source] Complementary action of jasmonic acid on salicylic acid in mediating fungal elicitor-induced flavonol glycoside accumulation of Ginkgo biloba cellsPLANT CELL & ENVIRONMENT, Issue 8 2009MAOJUN XU ABSTRACT The antagonistic action between jasmonic acid (JA) and salicylic acid (SA) in plant defence responses has been well documented. However, their relationship in secondary metabolite production is largely unknown. Here, we report that PB90, a protein elicitor from Phytophthora boehmeriae, triggers JA generation, SA accumulation and flavonol glycoside production of Ginkgo biloba cells. JA inhibitors suppress not only PB90-triggered JA generation, but also the elicitor-induced flavonol glycoside production. However, the elicitor can still enhance flavonol glycoside production even though the JA generation is totally inhibited. Over-expression of SA hydrolase gene NahG not only abolishes SA accumulation, but also suppresses the elicitor-induced flavonol glycoside production when JA signalling is inhibited. Interestingly, expression of NahG does not inhibit the elicitor-induced flavonol glycoside accumulation in the absence of JA inhibitors. Moreover, JA levels are significantly enhanced when SA accumulation is impaired in the transgenic cells. Together, the data suggest that both JA and SA are involved in PB90-induced flavonol glycoside production. Furthermore, we demonstrate that JA signalling might be enhanced to substitute for SA to mediate the elicitor-induced flavonol glycoside accumulation when SA signalling is impaired, which reveals an unusual complementary relationship between JA and SA in mediating plant secondary metabolite production. [source] Jasmonic acid treatment to part of the root system is consistent with simulated leaf herbivory, diverting recently assimilated carbon towards untreated roots within an hourPLANT CELL & ENVIRONMENT, Issue 9 2008GUNNAR JAKOB HENKES ABSTRACT It is known that shoot application of jasmonic acid (JA) leads to an increased carbon export from leaves to stem and roots, and that root treatment with JA inhibits root growth. Using the radioisotope 11C, we measured JA effects on carbon partitioning in sterile, split-root, barley plants. JA applied to one root half reduced carbon partitioning to the JA-treated tissue within minutes, whereas the untreated side showed a corresponding , but slower , increase. This response was not observed when instead of applying JA, the sink strength of one root half was reduced by cooling it: there was no enhanced partitioning to the untreated roots. The slower response in the JA-untreated roots, and the difference between the effect of JA and temperature, suggest that root JA treatment caused transduction of a signal from the treated roots to the shoot, leading to an increase in carbon allocation from the leaves to the untreated root tissue, as was indeed observed 10 min after the shoot application of JA. This supports the hypothesis that the response of some plant species to both leaf and root herbivores may be the diversion of resources to safer locations. [source] Root growth dynamics of Nicotiana attenuata seedlings are affected by simulated herbivore attackPLANT CELL & ENVIRONMENT, Issue 10 2007GRÉGOIRE M. HUMMEL ABSTRACT Many studies demonstrate resource-based trade-offs between growth and defence on a large timescale. Yet, the short-term dynamics of this growth reaction are still completely unclear, making it difficult to explain growth-defence trade-offs mechanistically. In this study, image-based non-destructive methods were used to quantify root growth reactions happening within hours following simulated herbivore attack. The induction of wound reactions in Nicotiana attenuata in the seedling stage led to transiently decreased root growth rates. Application of the oral secretion of the specialist herbivore Manduca sexta to the leaves led to a transient decrease in root growth that was more pronounced than if a mere mechanical wounding was imposed. Root growth reduction was more pronounced than leaf growth reduction. When fatty acid,amino acid conjugates (FACs) were applied to wounds, root growth reduction occurred in the same intensity as when oral secretion was applied. Timing of the transient growth reduction coincided with endogenous bursts of jasmonate (JA) and ethylene emissions reported in literature. Simulation of a wound response by applying methyl jasmonate (MeJA) led to more prolonged negative effects on root growth. Increased nicotine concentrations, trichome lengths and densities were observed within 72 h in seedlings that were treated with MeJA or that were mechanically wounded. Overall, these reactions indicate that even in a very early developmental stage, the diversion of plant metabolism from primary (growth-sustaining) to secondary (defence-related) metabolism can cause profound alterations of plant growth performance. [source] Using nutritional indices to study LOX3-dependent insect resistancePLANT CELL & ENVIRONMENT, Issue 8 2006CBGOWDA RAYAPURAM ABSTRACT Induced resistance to biotic attackers is thought to be mediated by responses elicited by jasmonic acid (JA), a subset of which are lipoxygenase 3 (LOX3) dependent. To understand the importance of LOX3-mediated insect resistance, we analysed the performance of Manduca sexta larvae on wild-type (WT) and on isogenic Nicotiana attenuata plants silenced in NaLOX3 expression and JA signalling, and we used Waldbauer nutritional indices to measure the pre- and post-ingestive effects. LOX3-mediated defenses reduced larval growth, consumption and frass production. These defenses reduced how efficiently late-instar larvae converted digested food to body mass (ECD). In contrast, LOX3-mediated defenses decreased approximate digestibility (AD) in early instar larvae without affecting the ECD and total food consumption. Larvae of all instars feeding on defended WT plants behaviourally compensate for their reduced body mass by consuming more food per unit of body mass gain. We suggest that larvae feeding on plants silenced in NaLOX3 expression (as-lox) initially increase their AD, which in turn enables them to consume more food in the later stages and consequently, to increase their ECD and efficiency of conversion of ingested food (ECI). We conclude that N. attenuata's oxylipin-mediated defenses are important for resisting attack from M. sexta larvae, and that Waldbauer nutritional assays reveal behavioural and physiological counter responses of insects to these plant defenses. [source] | |||||||||||||||||||