Evaluation of Simplified Leaf Inoculation Procedures for Identification of Quantitative Resistance to Sclerotinia trifoliorum in Alfalfa Seedlings

Previous studies established that excised leaf tissues of alfalfa can be inoculated with Sclerotinia trifoliorum to select for heritable resistance, but the original procedures were not practical for use in large-scale screening programs. In this study, simplified leaf inoculation procedures for more rapid screening for resistance, based on direct application of leaf tissues to colonies of the pathogen on agar media, were evaluated. Cotyledons, unifoliate leaves, and leaflets of trifoliolate leaves of plants 7 to 21 days old from three relatively susceptible cultivars and one resistant germ plasm were applied, with and without wounding, directly to colony margins of S. trifoliorum on cornmeal agar, V8 juice agar, and water agar. Leaves were scored according to the rate and extent of development of necrosis. Significant differences between alfalfa populations were expressed in unifoliate leaves and trifoliolate leaflets but not in cotyledons. Disease severity in the resistant germ plasm (Mississippi Sclerotinia-Resistant [MSR]) was less than in the three cultivars on all agar media. Wounding of leaf tissues increased disease severity and greatly reduced the incidence of symptomless leaves, which are indicated to be escapes, but wounding generally did not prevent expression of resistance in MSR. Results indicate that initial screening for resistance to S. trifoliorum in alfalfa seedlings may be accomplished by applying wounded unifoliate leaves and leaflets of trifoliolate leaves directly to colonies on cornmeal or V8 juice agars.

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Enhanced Resistance to Sclerotium rolfsii in Populations of Alfalfa Selected for Quantitative Resistance to Sclerotinia trifoliorum

Phytopathology ◽

10.1094/phyto.2002.92.2.204 ◽

2002 ◽

Vol 92 (2) ◽

pp. 204-209 ◽

Cited By ~ 10

Author(s):

R. G. Pratt ◽

D. E. Rowe

Keyword(s):

Quantitative Resistance ◽

Sclerotium Rolfsii ◽

Sclerotinia Trifoliorum ◽

Enhanced Resistance ◽

Inoculation Techniques ◽

Whole Plant ◽

Leaf Tissues ◽

Selection For ◽

Susceptible Populations ◽

Whole Plants

Sclerotinia trifoliorum and Sclerotium rolfsii are pathogens for which similar mechanisms of parasitism have been proposed. This suggested that resistance to these pathogens may be related in a common host plant. This study was undertaken to determine whether selection for quantitative resistance to Sclerotinia trifoliorum in alfalfa also increases resistance to Sclerotium rolfsii as expressed in excised leaf tissues and whole plants. Resistance in excised leaf tissues was evaluated according to the rate of necrosis induced by Sclerotium rolfsii following inoculation with mycelium. Resistance to Sclerotium rolfsii in whole plants was evaluated according to their survival following crown inoculations. Three alfalfa populations previously selected from cv. Delta for quantitative resistance to Sclerotinia trifoliorum exhibited enhanced resistance to Sclerotium rolfsii, in comparison with Delta or with susceptible populations, in excised leaf tissues. When whole plants of Delta and two of these populations, Sclerotinia trifoliorum resistant (STR) and Mississippi Sclerotinia resistant (MSR), were inoculated with Sclerotium rolfsii at 3 to 8 weeks of age, significant (P = 0.01) differences in survival were attributed to plant age at inoculation and alfalfa populations. Survival of both MSR and STR was significantly (P = 0.05) greater than for Delta; the best differential results were obtained by inoculating plants 5 to 7 weeks old. To evaluate relationships of resistance to Sclerotinia trifoliorum and Sclerotium rolfsii over a broader genetic background, additional populations were selected for resistance to Sclerotinia trifoliorum from four other alfalfa cultivars by leaf-inoculation techniques, and this resistance was confirmed by whole-plant inoculations. In excised leaf tissues, all four of these populations also expressed enhanced resistance to Sclerotium rolfsii in comparison with either parent cultivars or populations of comparable size selected at random. These results establish that selection for quantitative resistance to Sclerotinia trifoliorum in alfalfa also confers enhanced resistance to Sclerotium rolfsii as expressed in excised leaf tissues and whole plants. Results suggest, therefore, that genes for quantitative resistance to Sclerotinia trifoliorum and Sclerotium rolfsii in alfalfa are likely to be synonymous, overlapping, or closely linked.

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Periodontitis Is Related to Exercise Capacity: Two Cross-sectional Studies

Journal of Dental Research ◽

10.1177/0022034521995428 ◽

2021 ◽

pp. 002203452199542

Author(s):

B. Holtfreter ◽

B. Stubbe ◽

S. Gläser ◽

J. Trabandt ◽

H. Völzke ◽

...

Keyword(s):

Oxygen Uptake ◽

Disease Severity ◽

Cardiorespiratory Fitness ◽

Large Scale ◽

Cardiopulmonary Exercise Testing ◽

Exercise Duration ◽

Cross Sectional ◽

Sample Mean ◽

Cardiometabolic Diseases ◽

Number Of Teeth

Although a potential link between periodontitis and cardiorespiratory fitness might provide a reasonable explanation for effects of tooth-related alterations seen on cardiometabolic diseases, evidence is currently limited. Thus, we investigated the association between clinically assessed periodontitis and cardiopulmonary exercise testing (CPET). Data from 2 independent cross-sectional population-based studies (5-y follow-up of the Study of Health in Pomerania [SHIP-1; N = 1,639] and SHIP-Trend-0 [ N = 2,439]) were analyzed. Participants received a half-mouth periodontal examination, and teeth were counted. CPET was based on symptom limited-exercise tests on a bicycle ergometer. Associations of periodontitis parameters with CPET parameters were analyzed by confounder-adjusted multivariable linear regression. In the total sample, mean pocket probing depth (PPD), mean clinical attachment levels, and number of teeth were consistently associated with peak oxygen uptake (peakVO2) and exercise duration in both studies, even after restriction to cardiorespiratory healthy participants. Statistically significant associations with oxygen uptake at anaerobic threshold (VO2@AT), slope of the efficiency of ventilation in removing carbon dioxide, and peak oxygen pulse (VÉ/VCO2 slope) occurred. Further, interactions with age were identified, such that mainly older individuals with higher levels of periodontal disease severity were associated with lower peakVO2. Restricted to never smokers, associations with mean clinical attachment levels and the number of teeth mostly diminished, while associations of mean PPD with peakVO2, VO2@AT, VÉ/VCO2 slope, and exercise duration in SHIP-1 and SHIP-Trend-0 were confirmed. In SHIP-1, mean peakVO2 was 1,895 mL/min in participants with a mean PPD of 1.6 mm and 1,809 mL/min in participants with a mean PPD of 3.7 mm. To conclude, only mean PPD reflecting current disease severity was consistently linked to cardiorespiratory fitness in 2 cross-sectional samples of the general population. If confirmed in well-designed large-scale longitudinal studies, the association between periodontitis and cardiorespiratory fitness might provide a biologically plausible mechanism linking periodontitis with cardiometabolic diseases.

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Is Bisphosphonate-Related Osteonecrosis of the Jaw an Infection? A Histological and Microbiological Ten-Year Summary

International Journal of Dentistry ◽

10.1155/2014/452737 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 24

Author(s):

A. M. Hinson ◽

C. W. Smith ◽

E. R. Siegel ◽

B. C. Stack

Keyword(s):

Systematic Review ◽

Disease Severity ◽

Large Scale ◽

Clinical Signs ◽

Signs And Symptoms ◽

Osteonecrosis Of The Jaw ◽

Multifactorial Disease ◽

Clinical Signs And Symptoms ◽

Surgical Treatments

The role of infection in the etiology of bisphosphonate-related osteonecrosis of the jaw (BRONJ) is poorly understood. Large-scale epidemiological descriptions of the histology and microbiology of BRONJ are not found in the literature. Herein, we present a systematic review of BRONJ histology and microbiology (including demographics, immunocompromised associations, clinical signs and symptoms, disease severity, antibiotic and surgical treatments, and recovery status) validating that infection should still be considered a prime component in the multifactorial disease.

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Quantitative resistance loci to southern rust mapped in a temperate maize diversity panel

Phytopathology ◽

10.1094/phyto-04-21-0160-r ◽

2021 ◽

Author(s):

Guangchao Sun ◽

Ravi V. Mural ◽

Jonathan D. Turkus ◽

James C. Schnable

Keyword(s):

Disease Severity ◽

Quantitative Resistance ◽

Association Studies ◽

Disease Incidence ◽

Genome Wide Association Studies ◽

Maize Germplasm ◽

Photosynthetic Productivity ◽

Maize Diversity ◽

Puccinia Polysora ◽

Candidate Loci

Southern rust is a severe foliar disease of maize (Zea mays) resulting from infection with the obligate biotrophic fungus Puccinia polysora. This disease reduces photosynthetic productivity, which in turn reduces yields, with the greatest yield losses (up to 50%) associated with earlier onset infections. P. polysora urediniospores overwinter only in tropical and subtropical regions but cause outbreaks when environmental conditions favor initial infection. Increased temperatures and humidity during the growing season combined with an increased frequency of moderate winters are likely to increase the frequency of severe southern rust outbreaks in the US corn belt. In summer 2020, a severe outbreak of southern rust was observed in eastern Nebraska (NE), USA. We scored a replicated maize association panel planted in Lincoln, NE for disease severity and found that disease incidence and severity showed significant variation among maize genotypes. Genome-wide association studies identified four loci associated with significant quantitative variation in disease severity. These loci were associated with candidate genes with plausible links to quantitative disease resistance. A transcriptome-wide association study identified additional genes associated with disease severity. Together, these results indicate that substantial diversity in resistance to southern rust exists among current temperate-adapted maize germplasm, including several candidate loci that may explain the observed variation in resistance to southern rust.

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Impedance Screening for Preschool Children: State of the Art

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348947908800110 ◽

1979 ◽

Vol 88 (1) ◽

pp. 56-65 ◽

Cited By ~ 14

Author(s):

Jack L. Paradise ◽

Clyde G. Smith

Keyword(s):

Preschool Children ◽

Middle Ear ◽

Large Scale ◽

High Sensitivity ◽

Cutoff Point ◽

Screening Programs ◽

Large Numbers ◽

Middle Ear Disease ◽

High Degree ◽

Large Scale Screening

As a test for detecting middle ear disease among preschool children, tympanometry — as opposed to audiometry — has three advantageous attributes: a high degree of sensitivity, minimal need for subject cooperation, and total objectivity. For these reasons interest has arisen in tympanometry as a method for screening, i.e., identifying children with previously undetected middle ear disease. However, uncertainty persists concerning the importance of detecting apparently asymptomatic middle ear effusions, and concerning optimal methods, or even the advisability, of treating them. Further, the sensitivity and specificity of tympanometry depend on how the pass-fail cutoff point is defined. Defining this cutoff point so as to achieve high sensitivity may result in excessively low specificity, with the production of large numbers of false-positives who then become overreferrals. Data are presented to show how the validity of the test may be increased to some extent by attention to the gradient of “negative-pressure” tympanograms. At the present time, given the various aforementioned uncertainties, and with adequate validation as to the presence or absence of disease often lacking in reported studies of impedance screening in preschool populations, the cumulative results of these studies do not warrant embarking on large-scale screening programs. What is needed instead is additional research to explore the issue further.

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Clinical and Haplotypic Variability of Slovenian USH2A Patients Homozygous for the c. 11864G>A Nonsense Mutation

Genes ◽

10.3390/genes10121015 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1015 ◽

Cited By ~ 2

Author(s):

Andrej Zupan ◽

Ana Fakin ◽

Saba Battelino ◽

Martina Jarc-Vidmar ◽

Marko Hawlina ◽

...

Keyword(s):

Disease Severity ◽

Nonsense Mutation ◽

Age Of Onset ◽

Phenotypic Variability ◽

Fundus Autofluorescence ◽

Usher Syndrome ◽

Test Methods ◽

Rapid Screening ◽

Autofluorescence Imaging ◽

Phenotype Analysis

Purpose: to determine a detailed clinical and haplotypic variability of the Slovenian USH2A patients with homozygous c.11864G>A (p.Trp3955Ter) nonsense mutation and to develop sensitive, accurate and rapid screening test. Methods: Ten unrelated homozygous patients with detailed ophthalmological exam were included in our study. The High-Resolution Melting (HRM) method was developed for fast and reliable detection of the c.11864G>A mutation. Results: The c.11864G>A mutation represents the vast majority of pathogenic alleles in Slovenian USH2A-Usher syndrome population (84%). The median age of onset of nyctalopia was 16 years and all patients younger than 40 years had hyperautofluorescent rings on fundus autofluorescence imaging. The Kaplan Meier survival analysis showed a decline of central vision after the age of 40, with 50% patients reaching visual acuity (VA) ≤ 0.05 at the average age of 66 years visual field diameter less than 20° at the average age of 59 years. There was a relatively large phenotypic variability in the retinal and audiological phenotype. Analysis of the p.Trp3955Ter-homozygous patients revealed four different haplotypes, with the frequency of the most common haplotype ~65%. Disease severity did not correlate with the haplotype. Conclusions: According to the natural history of homozygous p.Trp3955Ter patients any therapy aimed to slow disease progression in these patients would be best started before the age of 40. Phenotypic variability suggests the presence of cis and/or trans factors outside the USH2A gene that are able to affect disease severity. High frequency of p.Trp3955Ter mutation in Slovenian USH2A gene pool appears to be initiated from different unrelated founders because of migrations from neighboring populations. The mutation on haplotype 2 seems to be the major founder allele.

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Pathogenic Viruses Commonly Present in the Oral Cavity and Relevant Antiviral Compounds Derived from Natural Products

Medicines ◽

10.3390/medicines5040120 ◽

2018 ◽

Vol 5 (4) ◽

pp. 120 ◽

Cited By ~ 4

Author(s):

Daisuke Asai ◽

Hideki Nakashima

Keyword(s):

Natural Products ◽

Oral Cavity ◽

Rational Design ◽

Large Scale ◽

Antiviral Agents ◽

Marine Sponges ◽

Design Strategies ◽

Screening Programs ◽

Human Oral Cavity ◽

Antiviral Compounds

Many viruses, such as human herpesviruses, may be present in the human oral cavity, but most are usually asymptomatic. However, if individuals become immunocompromised by age, illness, or as a side effect of therapy, these dormant viruses can be activated and produce a variety of pathological changes in the oral mucosa. Unfortunately, available treatments for viral infectious diseases are limited, because (1) there are diseases for which no treatment is available; (2) drug-resistant strains of virus may appear; (3) incomplete eradication of virus may lead to recurrence. Rational design strategies are widely used to optimize the potency and selectivity of drug candidates, but discovery of leads for new antiviral agents, especially leads with novel structures, still relies mostly on large-scale screening programs, and many hits are found among natural products, such as extracts of marine sponges, sea algae, plants, and arthropods. Here, we review representative viruses found in the human oral cavity and their effects, together with relevant antiviral compounds derived from natural products. We also highlight some recent emerging pharmaceutical technologies with potential to deliver antivirals more effectively for disease prevention and therapy.

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Large scale analyses of genotype-phenotype relationships of glycine decarboxylase mutations and neurological disease severity

PLoS Computational Biology ◽

10.1371/journal.pcbi.1007871 ◽

2020 ◽

Vol 16 (5) ◽

pp. e1007871

Author(s):

Joseph Farris ◽

Barbara Calhoun ◽

Md. Suhail Alam ◽

Shaun Lee ◽

Kasturi Haldar

Keyword(s):

Disease Severity ◽

Neurological Disease ◽

Large Scale ◽

Glycine Decarboxylase

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The Light and Shadow of Rapid Serological Tests for SARS-CoV-2 Infection: Results from a Study in a Large Emergency Department

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17186493 ◽

2020 ◽

Vol 17 (18) ◽

pp. 6493

Author(s):

Daniela Loconsole ◽

Francesca Centrone ◽

Caterina Morcavallo ◽

Silvia Campanella ◽

Anna Sallustio ◽

...

Keyword(s):

Emergency Department ◽

Real Time ◽

Real Time Pcr ◽

Respiratory Symptoms ◽

Large Scale ◽

Serological Test ◽

Serological Tests ◽

Serological Assay ◽

Infected People ◽

Screening Programs

A critical point in the management of the SARS-CoV-2 pandemic is the need to promptly identify the greatest number of infected people and to implement strict public health measures. In this study, the performance of a rapid serological test in a clinical setting was evaluated. Samples from 819 consecutive patients (with or without respiratory symptoms) admitted to a large Emergency Department were tested between 23 March and 21 April 2020. Patient samples were tested in a real-time PCR assay and a serological assay. In total, 148/819 patients (18.1%) tested positive for SARS-CoV-2 by real-time PCR. The serological test revealed that 70/819 patients (8.5%) had anti-SARS-CoV-2 IgM and/or IgG. The prevalence of anti-SARS-CoV-2 antibodies was significantly higher in patients with respiratory symptoms lasting for >7 days than in those with respiratory symptoms lasting for 0–7 days (p < 0.001). The serological assay had an overall sensitivity of 35.1% and an overall specificity of 97.3%. A high negative predictive value (96.7%) was reported for patients without respiratory symptoms. The results confirm that rapid serological assays alone are not sufficient for diagnosis of SARS-CoV-2 infection but can be incorporated into large-scale screening programs during periods in which the virus circulation is low.

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Effects of Herbicides on Diseases of Rice (Oryza sativa)

Weed Science ◽

10.1017/s0043174500033828 ◽

1977 ◽

Vol 25 (5) ◽

pp. 441-447 ◽

Cited By ~ 1

Author(s):

E. Inderawati ◽

R. Heitefuss

Keyword(s):

Oryza Sativa ◽

Disease Severity ◽

Culture Media ◽

Direct Action ◽

Culture Method ◽

Xanthomonas Oryzae ◽

Commercial Formulation ◽

Rice Plants ◽

Agar Media ◽

Rice Leaves

Seven herbicides were tested for their effect on growth of Pyricularia oryzae Cavara, Hypochnus sasakii Shirai, and Xanthomonas oryzae Uyeda & Ishiyama Dowson on agar media and for subsequent influence on disease intensity on rice plants (Oryza sativa L.) in the greenhouse. The herbicides studied were: propanil 3′,4′-dichloro-propionanilide), NTN 5$006 [O-(2-nitro-4-methylphenyl)-O-ethyl-N-isopropyl-phosphor-amidothioate], simetryn [2,4-bis(ethylamino)-6-)methylthio)-s-triazine], terbutryn [2-(tert-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine], nitrofen (2,4-dichlorophenyl-p-nitrophenyl ether), molinate (S-ethyl hexahydro-1H-azepine-1-carbothioate), and aglypt (4-amino-3-methylthio-6-phenyl-1,2,4-triazine-5-on). The growth of P. oryzae, H. sasakii and X. oryzae on culture media containing 10 μg/ml commercial formulation of propanil was reduced to approximately 50% of the control. The other herbicides tested were less effective. Differences in disease severity produced on rice plants treated with the previously mentioned herbicides were in agreement with the results obtained by the culture method. The effect of simetryn and nitrofen on disease severity was stronger than expected from the small direct action on the pathogen in culture. It is suggested that the influence of these two compounds on the disease intensity is due to their effect on the host plant rather than the pathogen directly. Propanil was effective only if applied immediately or up to 1 day before inoculation, indicating that this herbicide is degraded on or within the rice leaves.

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