Mapping spot blotch resistance genes in four barley populations

Bipolaris sorokiniana (teleomorph: Cochliobolus sativus) is the fungal pathogen responsible for spot blotch in barley (Hordeum vulgare L.) and occurs worldwide in warmer, humid growing conditions. Current Australian barley varieties are largely susceptible to this disease and attempts are being made to introduce sources of resistance from North America. In this study we have compared chromosomal locations of spot blotch resistance reactions in four North American two-rowed barley lines; the North Dakota lines ND11231-12 and ND11231-11 and the Canadian lines TR251 and WPG8412-9-2-1. Diversity Arrays Technology (DArT)-based PCR, expressed sequence tag (EST) and SSR markers have been mapped across four populations derived from crosses between susceptible parental lines and these four resistant parents to determine the location of resistance loci. Quantitative trait loci (QTL) conferring resistance to spot blotch in adult plants (APR) were detected on chromosomes 3HS and 7HS. In contrast, seedling resistance (SLR) was controlled solely by a locus on chromosome 7HS. The phenotypic variance explained by the APR QTL on 3HS was between 16 and 25% and the phenotypic variance explained by the 7HS APR QTL was between 8 and 42% across the four populations. The SLR QTL on 7HS explained between 52 to 64% of the phenotypic variance. An examination of the pedigrees of these resistance sources supports the common identity of resistance in these lines and indicates that only a limited number of major resistance loci are available in current two-rowed germplasm

Effects of Antiepileptic Drugs on GABA Responses and on Reduction of GABA Responses by PTZ and DMCM on Mouse Neurons in Cell Culture

The mechanisms of action of antiepileptic drugs effective against generalized absence seizures (antiabsence AEDs) remain uncertain. Antiabsence AEDs are generally effective against seizures induced in experimental animals by pentylenÉtÉtrazol (PTZ) and methyl-6,7-dimethoxy-4-ethyl-Β-carboline-3-carboxylate (DMCM), drugs which reduce GABAergic inhibition. Thus, antiabsence AEDs have been suggested to enhance GABAergic inhibition. We studied the effects of several AEDs on GABA responses recorded from mouse spinal cord neurons grown in primary dissociated cell culture. Four antiabsence AEDs were included: ethosuximide (ESM), dimethadione (DMO), sodium valproate (VPA), and diazepam (DZP). Two experimental AEDs, CGS 9896 and ZK 91296, with anticonvulsant action against PTZ- or DMCM-induced seizures were also included. Possible effects of the antiabsence and experimental AEDS on PTZ- and DMCM-induced inhibition of GABA responses were also evaluated. PTZ and DMCM revers-ibly reduced GABA responses in a concentration-dependent manner. PTZ complÉtÉly inhibited GABA responses at 10 mM (IC 50 of 1.1 mM), whereas DMCM-induced inhibition of GABA responses reached a plateau level of 39% of control values at 1 p.M (IC 50 of 33 nM). ESM (1,200 ΜM), DMO (6 mM), VPA (200 u.M), CGS 9896 (2 ΜM), and ZK 98% (2 Μ M ) did not alter GABA responses. DZP enhanced GABA responses in a concentration-dependent manner. The inhibition of GABA responses produced by PTZ 1 mM was unaltered by ESM (600 Μ M ), DMO (6 mM), CGS 9896 (1 Μ M), or ZK 9896 (1 ΜM)- Coapplication of VPA (200 ΜM) and PTZ (1 mM) slightly enhanced the PTZ effect. DZP (> 10 nM), however, reversed the PTZ-induced reduction of GABA responses. The DMCM (250 nM) inhibition of GABA-responses was unaltered by ESM (600 Μ.M), DMO (2 mM), or VPA (200 ΜM). CGS 9896 (2 Μ M ) and ZK 91296 (2 ΜM), however, antagonized the DMCM effect. DZP (> 10 nM) significantly reversed the DMCM-induced inhibition of GABA responses. The lack of effect of VPA, ESM, and DMO on postsynaptic GABA responses suggests that direct enhancement of postsynaptic GABA action is not a common mechanism of action of antiabsence AEDs. The AEDs DZP, CGS 98%, and ZK 912% all reversed DMCM, but not PTZ, reduction of GABA responses, suggesting that these AEDs blocked DMCM seizures by acting at benzodiazepine receptors. However, since only DZP enhanced GABA responses, it is unclear how CGS 98% and ZK 912% blocked PTZ seizures. Key Words: Anticonvulsants–GABA–Neuron culture–Cell culture–Spinal cord neurons–Convulsants. RESUMEN Los mecanismos de accidn de las medicaciones antiepilÉpticas eficaces contra los ataques generalizados de ausencia (AEDs antiausencia) permanecen inciertos. Los AEDs antiausencia son, generalmente, eficaces contra ataques experimentales inducidos por el pentilentetrazol (PTZ) y el metil-6,7-dimetoxy-4-etil-Pcarbolina-3-carboxilato (DMCM) en animates, medicaciones que reducen la inhibiciÓn GABAÉrgica. Hemos estudiado los efectos de varios AEDs sobre respuestas-GABA registradas en las neuronas de la mÉdula espinal de ratones que habian crecido en cultivos de cÉlulas primarieas disociadas. Cuatro AEDs antiausencia fueron incluidos: etoxusimida (ESM), dimetadiona (DMO), valproato sÓdico (VPA) y diazepan (DZP). TambtÉn se incluyeron dos AEDs experimentales, CGS 9896 y ZK 912%, con acciÓn anticonvulsiva contra los ataques inducidos por PTZ o DMCM. TambiÓn se valoraron los posibles efectos de los AEDs antiausencia y experimentales sobre el PTZ y la inhibiciÓn de las respuestas-GABA inducidas por el DMCM. El PTZ y el DMCM redujeron las respuestas-GABA de modo reversible y dependiendo de sus concentraciones. El PTZ inhibiÓ cmpleta-mente las respuestas-GABA a 10 mM (IC 50 de 1.1 mM) mientras que la inhibitiÓn de las respuestas GABA inducida por el DMCM alcanzÓ un nivel estable del 39% de los valores control con 1 Μ. M (IC 50 de 33 mM). La ESM (1200 Μ.M), la DMO (6 mM), el VPA (200 Μ M ), el CGS 98% (2 Μ M) y el ZK 98% (2 Μ M) no alteraron las respuestas-GABA. El DZP aumentÓ las respuestas GABA de una manera concentraciÓn-dependiente. La inhibition de las respuestas-GABA producidas por el PTZ (1 mM), no se altero con las ESM (600 Μ M), la DMO (6 mM), el CGS 98% (1 Μ M) o el ZK 98% (1 Μ .M). La co-aplicacion de VPA (200 Μ M) y el PTZ (1 mM) aument6 ligeramente los efectos del PTZ. Sin embargo el DZP (10 nM) revirtiÓ significativamente la inhibition de las respuestas GABA inducidas por el DMCM. La falta de efectos de CPA, ESM y DMO sobre las respuestas GABA post-sinÁpticas sugiere que el incremento de la acciÓn GABA post-sinÁptica no es un mecanismo comÚn de actuatiÓn de las AEDs antiausencia. Todas las AEDs DZP, CGS 98% y ZK 912% revirtieron la reduction de las respuestas GABA producidas por el DMCM pero no las inducidas por el PTZ lo que sugiere que estos AEDs bloquean los ataques DMCM actuando sobre los receptores de la benzodiazepina. Sin embargo, puesto que el incremento de las respuestas GABA sÓlÓ se produce por el DZP, permanece todavia sin aclarar el por quÉ el CGS 98% y el ZK 912% bloquean los ataques producidos por el PTZ. ZUSAMMENFASSUNG Der Wirkmechansimus von Antiepileptika gegen generalisierte Absencen ist unklar. Antiabsencemittel sind generell wirkungs-voll gegen PTZ- und Methyl-6,7-Dimethoxy-4-Äthyl-P-Carbolin-Β-Carboxylat (DMCM) induzierte tierexperimentelle AnfÄlle, also von Medikamenten, die die GABA-erge Inhibition reduzieren. Es wurde vermutet, daß Antiabsencemittel die GABA-erge Inhibition verstÄrken. Wir untersuchten die Wirkung von verschiedenen Antiepileptika auf GABA-Antworten in spinalen MÄuseneuronen, die in Zellkulturen gew-achsen waren. Es wurden 4 Absencemittel untersucht: Ethosux-imid (ESM), Dimethadion (DMD), Sodium Valproat (VPA) und Diazepam (DZP). ZusÄtzlich wurden 2 experimentelle Antiepileptika, CGS 98% und ZK 912%, die gegen PTZ0 oder DMCM-induzierte AnfÄlle wirkungsvoll sind, eingeschlossen. Mogliche Wirkungen der Antiabsence- und experimentellen Antiepileptika auf PTZ- und DMCM-induzierte Hemmung der GABA-Antworten wurden ebenfalls ausgewertet. PTZ und DMCM zeigten eine konzentrationsabhÄngige reversible Reduktion der GABA-Antworten. PTZ zeigte eine komplette Hemmung der GABA-Antworten bei 10 mM (IC 50 1,1 mM), DMCM-Hemmung der GABA-Antworten zeigte ein Plateau von 39% der Kontroll-werte bei 1 uJtf (ICJO von 33 mAfl. ESM (1200 uJtf), DMD (6 mM), VPA (200 Μ M), CGS 98% (2 Μ M) und ZK 98% (2 Μ M) anderten nicht die GABA-Antworten. DZP verstarkte die GABA-Antworten konzentrationsabhangig. Die durch PTZ (1 mM) hervorgerufene Hemmung der GABA-Antworten war bei ESM (600 Μ M), DMD (6 mM), CGS 98% (1 mAO und ZK 3836 (1 mM) unverÄndert. ZusÄtliche Anwendung von VPA (200 mM) und PTZ (1 mM) verstÄrkten geringfÜgig den PTZ-Effekt. DZP (10 nM) kehrte die durch PTZ hervorgerufene Reduktion der GABA-Antworten um. Die durch DMCM (250 nM) hervorgerufene Hemmung der GABA-Antworten war durch ESM (600 Μ .M), DMD (2 mM) und VPA (200 Μ M ) unbeeinflusst. CGS 98% (2 Μ M) und ZK 912% (2 Μ M ) antagonisierten die DMCM-Wirkung. DZP (>10 nM) kehrte die durch DMCM-induzierte Hemmung der GABA-Antworten um. Das Fehlen einer Wirkung von VPA. ESM und DMD auf die postsynaptischen GABA-Antworten legen nahe, daß eine direkte VerstÄrkung der postsynaptischen GABA-Aktion kein gemeinsamer Mechanis-mus der Antiabsencemittel darstellt. Die Antiepileptika DZP, CGS 98% und ZK 912% kehrten die DMCM-Wirkung auf die GABA-Antworten um, jedoch nicht die von PTZ, was vermuten lapt, daß diese Antiepileptika die DMCM-AnfÄlle Über die Wirkung an den Benzodiazipin-Rezeptoren verhinderte. Da jedoch nur DZP GABA-Antworten verstarkte, ist unklar, in welcher Weise CGS 98% und ZK 912% die PTZ-AnfaUe ver-hinderten.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65188/1/j.1528-1157.1989.tb05275.x.pd

Morphological and molecular characterization of Curvularia and related species associated with leaf spot disease of rice in Peninsular Malaysia

Curvularia species are important phytopathogens reported worldwide. They are closely related; consist of major destructive pathogens mainly for grasses and cereal plants including rice (Oryza sativa). A leaf spot symptom of rice is one of the common symptoms found in the rice field and caused reduction of rice yield. However, there are no reports on Curvularia species associated with rice leaves showing spot symptoms. The objectives are to isolate and characterize Curvularia and related species from leaf spot of rice by using morphological and molecular characterization and to determine the phylogenetic relationship between the isolated fungi. Fungal isolation was done from diseased rice leaves showing leaf spot symptoms collected throughout Peninsular Malaysia. Thirty-three isolates were recovered and identified based on their morphological characteristics such as conidia morphology, colony appearance, pigmentation and growth rate for species delimitation. Internal transcribed spacer (ITS) region was amplified to confirm the species identification. The 33 isolates were identified as Bipolaris sorokiniana (10 isolates), Curvularia hawaiiensis (8 isolates), C. geniculata (6 isolates), C. eragrostidis (6 isolates), C. aeria (2 isolates) and C. lunata (1 isolate). A phylogenetic tree was constructed based on ITS sequences using neighbour-joining method. The tree grouped members of Curvularia and Bipolaris into different clades. The phylogenetic tree indicated that the presence of two groups of fungi species; highly virulent and mild pathogens. In conclusion, Curvularia species and Bipolaris sorokiniana were present in rice field in Malaysia and associated with leaf spot of rice

Can CAPTURE be used to identify undiagnosed patients with mild-to-moderate COPD likely to benefit from treatment?

Nancy K Leidy,1 Fernando J Martinez,2 Karen G Malley,1 David M Mannino,3 MeiLan K Han,4 Elizabeth D Bacci,5 Randall W Brown,6 Julia F Houfek,7 Wassim W Labaki,4 Barry J Make,8 Catherine A Meldrum,4 Wilson Quezada,9 Stephen Rennard,10 Byron Thomashow,9 Barbara P Yawn11 1Evidera, Patient-Centered Research, Bethesda, MD, USA; 2Weill Cornell Medicine, Joan & Sanford Weill Department of Medicine, New York, NY, USA; 3University of Kentucky, Preventive Medicine & Environmental Health, Lexington, KY, USA; 4University of Michigan, Division of Pulmonary & Critical Care Medicine, Ann Arbor, MI, USA; 5Evidera, Patient-Centered Research, Seattle, WA, USA; 6University of Michigan, Department of Health Behavior & Health Education, School of Public Health, Ann Arbor, MI, USA; 7University of Nebraska Medical Center College of Nursing, Omaha, NE, USA; 8National Jewish Health, Department of Medicine, Division of Pulmonary, Critical Care & Sleep Medicine, Denver, CO, USA; 9Columbia University Medical Center, Division of Pulmonary, Allergy, & Critical Care, New York, NY, USA; 10AstraZeneca, IMED Biotech Unit, Cambridge, UK & University of Nebraska Medical Center, Department of Medicine, Omaha, NE, USA; 11University of Minnesota, Department of Family & Community Health, Minneapolis, MN & COPD Foundation, Miami, FL, USA Background: COPD Assessment in Primary Care To Identify Undiagnosed Respiratory Disease and Exacerbation Risk (CAPTURE™) uses five questions and peak expiratory flow (PEF) thresholds (males ≤350 L/min; females ≤250 L/min) to identify patients with a forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) <0.70 and FEV1 <60% predicted or exacerbation risk requiring further evaluation for COPD. This study tested CAPTURE’s ability to identify symptomatic patients with mild-to-moderate COPD (FEV1 60%–80% predicted) who may also benefit from diagnosis and treatment. Methods: Data from the CAPTURE development study were used to test its sensitivity (SN) and specificity (SP) differentiating mild-to-moderate COPD (n=73) from no COPD (n=87). SN and SP for differentiating all COPD cases (mild to severe; n=259) from those without COPD (n=87) were also estimated. The modified Medical Research Council (mMRC) dyspnea scale and COPD Assessment Test (CAT™) were used to evaluate symptoms and health status. Clinical Trial Registration: NCT01880177, https://ClinicalTrials.gov/ct2/show/NCT01880177?term=NCT01880177&rank=1. Results: Mean age (+SD): 61 (+10.5) years; 41% male. COPD: FEV1/FVC=0.60 (+0.1), FEV1% predicted=74% (+12.4). SN and SP for differentiating mild-to-moderate and non-COPD patients (n=160): Questionnaire: 83.6%, 67.8%; PEF (≤450 L/min; ≤350 L/min): 83.6%, 66.7%; CAPTURE (Questionnaire+PEF): 71.2%, 83.9%. COPD patients whose CAPTURE results suggested that diagnostic evaluation was warranted (n=52) were more likely to be symptomatic than patients whose results did not (n=21) (mMRC >2: 37% vs 5%, p<0.01; CAT>10: 86% vs 57%, p<0.01). CAPTURE differentiated COPD from no COPD (n=346): SN: 88.0%, SP: 83.9%. Conclusion: CAPTURE (450/350) may be useful for identifying symptomatic patients with mild-to-moderate airflow obstruction in need of diagnostic evaluation for COPD. Keywords: COPD, case-finding, undiagnosed COPD, screening tool, peak expiratory flo