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1.
Phys Rev Lett ; 123(9): 092502, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31524489

RESUMO

The most remote isotope from the proton dripline (by 4 atomic mass units) has been observed: ^{31}K. It is unbound with respect to three-proton (3p) emission, and its decays have been detected in flight by measuring the trajectories of all decay products using microstrip detectors. The 3p emission processes have been studied by the means of angular correlations of ^{28}S+3p and the respective decay vertices. The energies of the previously unknown ground and excited states of ^{31}K have been determined. This provides its 3p separation energy value S_{3p} of -4.6(2) MeV. Upper half-life limits of 10 ps of the observed ^{31}K states have been derived from distributions of the measured decay vertices.

2.
Plant Dis ; 102(2): 421-427, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30673516

RESUMO

Since 1984, the 'Chilero' spring wheat line developed by CIMMYT has proven to be highly resistant to leaf rust and stripe rust. Amid efforts to understand the basis of resistance of this line, a recombinant inbred line (RIL) population derived from a cross between Avocet and Chilero was studied. The parents and RILs were characterized in field trials for leaf rust and stripe rust in three locations in Mexico between 2012 and 2015 and genotyped with DArT-array, DArT-GBS, and SSR markers. A total of 6,168 polymorphic markers were used to construct genetic linkage maps. Inclusive composite interval mapping detected four colocated resistance loci to both rust diseases and two stripe rust resistant loci in the Avocet × Chilero population. Among these, the quantitative trait locus (QTL) on chromosome 1BL was identified as a pleotropic adult plant resistance gene Lr46/Yr29, whereas QLr.cim-5DS/QYr.cim-5DS was a newly discovered colocated resistance locus to both rust diseases in Chilero. Additionally, one new stripe rust resistance locus on chromosome 7BL was mapped in the current population. Avocet also contributed two minor colocated resistance QTLs situated on chromosomes 1DL and 4BS. The flanking SNP markers can be converted to breeder friendly Kompetitive Allele Specific PCR (KASP) markers for wheat breeding programs.


Assuntos
Basidiomycota/fisiologia , Resistência à Doença/genética , Genes de Plantas/genética , Doenças das Plantas/genética , Triticum/genética , Mapeamento Cromossômico , Genótipo , México , Locos de Características Quantitativas , Triticum/microbiologia
3.
Plant Dis ; 101(3): 456-463, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30677352

RESUMO

Leaf rust (LR) and stripe rust (YR) are important diseases of wheat worldwide. We used 148 recombinant inbred lines (RIL) from the cross of Avocet × Kundan for determining and mapping the genetic basis of adult plant resistance (APR) loci. The population was phenotyped LR and YR for three seasons in field trials conducted in Mexico and genotyped with the diversity arrays technology sequencing (DArT-Seq) and simple sequence repeat markers. The final genetic map was constructed using 2,937 polymorphic markers with an average distance of 1.29 centimorgans between markers. Inclusive composite interval mapping identified two co-located APR quantitative trait loci (QTL) for LR and YR, two LR QTL, and three YR QTL. The co-located resistance QTL on chromosome 1BL corresponded to the pleiotropic APR gene Lr46/Yr29. QLr.cim-2BL, QYr.cim-2AL, and QYr.cim-5AS could be identified as new resistance loci in this population. Lr46/Yr29 contributed 49.5 to 65.1 and 49.2 to 66.1% of LR and YR variations, respectively. The additive interaction between detected QTL showed that LR severities for RIL combining four QTL ranged between 5.3 and 25.8%, whereas the lowest YR severities were for RIL carrying QTL on chromosomes 1BL + 2AL + 6AL. The high-density DArT-Seq markers across chromosomes can be used in fine mapping of the targeted loci and development SNP markers.

4.
Field Crops Res ; 192: 78-85, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27307654

RESUMO

Maintaining wheat productivity under the increasing temperatures in South Asia is a challenge. We focused on developing early maturing wheat lines as an adaptive mechanism in regions suffering from terminal heat stress and those areas that require wheat adapted to shorter cycles under continual high temperature stress. We evaluated the grain yield performance of early-maturing heat-tolerant germplasm developed by CIMMYT, Mexico at diverse locations in South Asia from 2009 to 2014 and estimated the breeding progress for high-yielding and early-maturing heat-tolerant germplasm in South Asia. Each year the trial comprised of 28 new entries, one CIMMYT check (Baj) and a local check variety. Locations were classified by mega environment (ME); ME1 being the temperate irrigated locations with terminal high temperature stress, and ME5 as hot, sub-tropical, irrigated locations. Grain yield (GY), days to heading (DTH) and plant height (PH) were recorded at each location. Effect of temperature on GY was observed in both ME1 and ME5. Across years, mean minimum temperatures in ME1 and mean maximum temperatures in ME5 during grain filling had significant negative association with GY. The ME1 locations were cooler that those in ME5 in the 5 years of evaluations and had a 1-2 t/ha higher GY. A mean reduction of 20 days for DTH and 20 cm in PH was observed in ME5. Negative genetic correlations of -0.43 to -0.79 were observed between GY and DTH in South Asia during 2009-2014. Each year, we identified early-maturing germplasm with higher grain yield than the local checks. A positive trend was observed while estimating the breeding progress across five years for high-yielding early-maturing heat tolerant wheat compared to the local checks in South Asia. The results suggests the potential of the high-yielding early-maturing wheat lines developed at CIMMYT in improving wheat production and maintaining genetic gains in South Asia.

5.
Phys Rev Lett ; 115(20): 202501, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26613434

RESUMO

Previously unknown isotopes (30)Ar and (29)Cl have been identified by measurement of the trajectories of their in-flight decay products (28)S+p+p and (28)S+p, respectively. The analysis of angular correlations of the fragments provided information on decay energies and the structure of the parent states. The ground states of (30)Ar and (29)Cl were found at 2.25(-0.10)(+0.15) and 1.8±0.1 MeV above the two- and one-proton thresholds, respectively. The lowest states in (30)Ar and (29)Cl point to a violation of isobaric symmetry in the structure of these unbound nuclei. The two-proton decay has been identified in a transition region between simultaneous two-proton and sequential proton emissions from the (30)Ar ground state, which is characterized by an interplay of three-body and two-body decay mechanisms. The first hint of a fine structure of the two-proton decay of (30)Ar*(2(+)) has been obtained by detecting two decay branches into the ground and first-excited states of the (28)S fragment.

6.
Plant Dis ; 99(4): 508-511, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30699549

RESUMO

Stripe rust, caused by Puccinia striiformis f. sp. tritici W., is a devastating disease of wheat worldwide. A new stripe rust resistance gene with moderate seedling and adult plant resistance was mapped using an F5 recombinant inbred line (RIL) population developed from the cross of the resistant parent 'Almop' with the susceptible parent 'Avocet'. The parents and RILs were phenotyped for seedling stripe rust response variation in a greenhouse and in field trials at Toluca, Mexico for 2 years. Almop showed moderate levels of resistance at both seedling and adult plant stages compared with the highly susceptible response of Avocet. The distribution of homozygous resistant, homozygous susceptible, and segregating RILs conformed to segregation at a single locus. Seedlings and adult plant responses were correlated, indicating that the same gene conferred resistance at both stages. A bulk segregant analysis approach with widely distributed simple sequence repeat (SSR) markers mapped the resistance gene to the distal region of the long arm of chromosome 4A. The SSR marker wmc776 cosegregated with this gene, whereas markers wmc219 and wmc313 were tightly linked and both located at 0.6 centimorgans. The resistance locus was designated Yr60.

7.
Plant Dis ; 99(8): 1153-1160, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30695943

RESUMO

The Kenyan wheat (Triticum aestivum L.) 'Kenya Kongoni' exhibits high levels of adult plant resistance (APR) to leaf rust (LR) and yellow rust (YR). We determined the genomic regions associated with LR and YR resistance in a population of 148 recombinant inbred lines generated from a cross between 'Avocet-YrA' and Kenya Kongoni. Field experiments to characterize APR to LR and YR were conducted in four and two Mexican or Uruguayan environments, respectively. A linkage map was constructed with 438 diversity arrays technology and 16 simple-sequence repeat markers by JoinMap 4.1 software. Genetic analyses showed that resistance to both rusts was determined by four to five APR genes, including Lr46/Yr29 and Sr2/Lr27/Yr30. Quantitative trait loci (QTL) analysis indicated that pleiotropic APR loci QYLr.cim-1BL corresponding to Lr46/Yr29 and QYLr.cim-7BL that is a putative novel QTL accounted for 5 to 57% and 12 to 35% of the phenotypic variation for resistance to LR and YR, respectively. These loci, in combination with another three LR QTL and two YR QTL, respectively, conferred high levels of resistance to both LR and YR in wheat under Mexican and Uruguayan environments. Among other detected QTL, QLr.cim-1DS, QLr.cim-2BL, and QYLr.icm-7BL may be new loci for APR to both rusts in common wheat.

8.
Plant Dis ; 98(9): 1227-1234, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30699610

RESUMO

Leaf rust and stripe rust are important diseases of wheat and can be controlled by growing resistant varieties. We investigated the genetic basis of resistance to both rusts in 198 F5 recombinant inbred lines derived from a cross between 'Avocet' and 'Francolin#1'. The population was phenotyped in greenhouse and field, and genotyped with known gene-associated molecular markers. Seedling resistance of Francolin#1 to leaf and stripe rusts was attributed to the loosely linked genes Lr16 and YrF, respectively, with a recombination frequency of 0.36. Field segregation indicated that adult plant resistance (APR) to leaf and stripe rusts was conferred by three and five additive genes, respectively. Among them, Lr46/Yr29 was associated with resistance to both rusts in Francolin#1, Lr16 reduced field leaf rust severity by 8 to 9%, and YrF contributed to 10 to 25% reductions in stripe rust severity. The Lr16 region was also associated with a 5 to 16% reduction in stripe rust severity, which is likely due to its linkage with YrF or another unidentified stripe rust APR gene. Significant additive effects on stripe rust were detected between YrF and Yr29. We conclude that APR in Francolin#1 to leaf and stripe rusts involves a combination of seedling and APR genes.

9.
Plant Dis ; 98(5): 631-635, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-30708548

RESUMO

Leaf rust, caused by Puccinia triticina (Pt), has become a globally important disease for durum wheat (Triticum turgidum subsp. durum) since the detection of race group BBG/BN, which renders ineffective a widely deployed seedling resistance gene present in several popular cultivars including Mexican cultivars Altar C84 and Atil C2000. The resistance gene continues to play a key role in protecting durum wheat against bread wheat-predominant races since virulence among this race group has not been found. We developed F3 and F5 mapping populations from a cross between Atil C2000 and the susceptible line Atred #1. Resistance was characterized by greenhouse seedling tests using three Pt races. Segregation tests indicated the presence of a single gene, which was mapped to the distal end of 7BS by bulk segregant analysis. The closest marker, wmc606, was located 5.5 cM proximal to the gene. No known leaf rust resistance genes are reported in this region; this gene was therefore designated as Lr72. The presence of Lr72 was further investigated in greenhouse tests in a collection of durum wheat using 13 Pt races. It was concluded that at least one additional gene protects durum wheat from bread wheat-predominant Pt races.

10.
Semergen ; 50(6): 102220, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38554607

RESUMO

OBJECTIVE: To determine the prevalence, impact and management of hypertension-mediated organ damage (HMOD) according to the presence of type 2 diabetes (T2DM). METHODS: IBERICAN is an ongoing multicenter, observational and prospective study, including outpatients aged 18-85 years who attended the Primary Care setting in Spain. In this study, the prevalence, impact and management of HMOD according to the presence of T2DM at baseline were analyzed. RESULTS: At baseline, 8066 patients (20.2% T2DM, 28.6% HMOD) were analyzed. Among patients with T2DM, 31.7% had hypertension, 29.8% dyslipidemia and 29.4% obesity and 49.3% had ≥1 HMOD, mainly high pulse pressure (29.6%), albuminuria (16.2%) and moderate renal impairment (13.6%). The presence of T2DM significantly increased the risk of having CV risk factors and HMOD. Among T2DM population, patients with HMOD had more dyslipidemia (78.2% vs 70.5%; P=0.001), hypertension (75.4% vs 66.4%; P=0.001), any CV disease (39.6% vs 16.1%; P=0.001) and received more drugs. Despite the majority of types of glucose-lowering agents were more frequently taken by those patients with HMOD, compared to the total T2DM population, the use of SGLT2 inhibitors and GLP-1 receptor agonists was marginal. CONCLUSIONS: In patients daily attended in primary care setting in Spain, one in five patients had T2DM and nearly half of these patients had HMOD. In patients with T2DM, the presence of HMOD was associated with a higher risk of CV risk factors and CV disease. Despite the very high CV risk, the use of glucose-lowering agents with proven CV benefit was markedly low.


Assuntos
Diabetes Mellitus Tipo 2 , Dislipidemias , Hipertensão , Atenção Primária à Saúde , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Pessoa de Meia-Idade , Masculino , Idoso , Feminino , Hipertensão/epidemiologia , Espanha/epidemiologia , Prevalência , Estudos Prospectivos , Adulto , Idoso de 80 Anos ou mais , Dislipidemias/epidemiologia , Adulto Jovem , Adolescente , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Fatores de Risco , Obesidade/complicações , Obesidade/epidemiologia , Hipoglicemiantes
11.
Theor Appl Genet ; 126(10): 2427-49, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23955314

RESUMO

Over thirty publications during the last 10 years have identified more than 140 QTLs for stripe rust resistance in wheat. It is likely that many of these QTLs are identical genes that have been spread through plant breeding into diverse backgrounds through phenotypic selection under stripe rust epidemics. Allelism testing can be used to differentiate genes in similar locations but in different genetic backgrounds; however, this is problematic for QTL studies where multiple loci segregate from any one parent. This review utilizes consensus maps to illustrate important genomic regions that have had effects against stripe rust in wheat, and although this methodology cannot distinguish alleles from closely linked genes, it does highlight the extent of genetic diversity for this trait and identifies the most valuable loci and the parents possessing them for utilization in breeding programs. With the advent of cheaper, high throughput genotyping technologies, it is envisioned that there will be many more publications in the near future describing ever more QTLs. This review sets the scene for the coming influx of data and will quickly enable researchers to identify new loci in their given populations.


Assuntos
Basidiomycota/fisiologia , Resistência à Doença/imunologia , Doenças das Plantas/microbiologia , Locos de Características Quantitativas/genética , Triticum/genética , Triticum/microbiologia , Mapeamento Cromossômico , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Triticum/imunologia
12.
Theor Appl Genet ; 126(7): 1721-32, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23558982

RESUMO

Chapio is a spring wheat developed by CIMMYT in Mexico by a breeding program that focused on multigenic resistances to leaf rust and stripe rust. A population consisting of 277 recombinant inbred lines (RILs) was developed by crossing Chapio with Avocet. The RILs were genotyped with DArT markers (137 randomly selected RILs) and bulked segregant analysis conducted to supplement the map with informative SSR markers. The final map consisted of 264 markers. Phenotyping against stripe rust was conducted for three seasons in Toluca, Mexico and at three sites over two seasons (total of four environments) in Sichuan Province, China. Significant loci across the two inter-continental regions included Lr34/Yr18 on 7DS, Sr2/Yr30 on 3BS, and a QTL on 3D. There were significant genotype × environment interactions with resistance gene Yr31 on 2BS being effective in most of the Toluca environments; however, a late incursion of a virulent pathotype in 2009 rendered this gene ineffective. This locus also had no effect in China. Conversely, a 5BL locus was only effective in the Chinese environments. There were also complex additive interactions. In the Mexican environments, Yr31 suppressed the additive effect of Yr30 and the 3D locus, but not of Lr34/Yr18, while in China, the 3D and 5BL loci were generally not additive with each other, but were additive when combined with other loci. These results indicate the importance of maintaining diverse, multi-genic resistances as Chapio had stable inter-continental resistance despite the fact that there were QTLs that were not effective in either one or the other region.


Assuntos
Resistência à Doença/genética , Locos de Características Quantitativas , Triticum/genética , China , Cruzamentos Genéticos , Meio Ambiente , Marcadores Genéticos , Genótipo , México , Doenças das Plantas/microbiologia , Triticum/microbiologia
13.
Plant Dis ; 97(6): 728-736, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30722591

RESUMO

Identifying and utilizing rust resistance genes in wheat has been hampered by the continuous and rapid emergence of new pathogen races. A major focus of many wheat breeding programs is achieving durable adult plant resistance (APR) to yellow (stripe) rust (YR) and leaf (brown) rust (LR), caused by Puccinia striiformis and P. triticina, respectively. This study aimed to determine the genetic basis of resistance to YR and LR in the common spring wheat 'Quaiu 3'. To that end, we evaluated 198 F5 recombinant inbred lines (RILs), derived from a cross of susceptible 'Avocet-YrA' with Quaiu 3, for APR to LR and YR in artificially inoculated field trials conducted in Mexico during the 2009 and 2010 growing seasons. High narrow-sense heritability (h2) estimates, ranging between 0.91 and 0.95, were obtained for both LR and YR disease severities for both years. The quantitative and qualitative approaches used to estimate gene numbers showed that, in addition to known resistance genes, there are at least two to three APR genes associated with LR and YR resistance in the RIL population. The moderately effective race-specific resistance gene Lr42 and the pleiotropic slow-rusting APR gene Lr46/Yr29 were found to interact with additional unidentified APR genes. The unidentified APR genes should be of particular interest for further characterization through molecular mapping, and for utilization by wheat breeding programs.

14.
medRxiv ; 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37461674

RESUMO

Our ability to forecast epidemics more than a few weeks into the future is constrained by the complexity of disease systems, our limited ability to measure the current state of an epidemic, and uncertainties in how human action will affect transmission. Realistic longer-term projections (spanning more than a few weeks) may, however, be possible under defined scenarios that specify the future state of critical epidemic drivers, with the additional benefit that such scenarios can be used to anticipate the comparative effect of control measures. Since December 2020, the U.S. COVID-19 Scenario Modeling Hub (SMH) has convened multiple modeling teams to make 6-month ahead projections of the number of SARS-CoV-2 cases, hospitalizations and deaths. The SMH released nearly 1.8 million national and state-level projections between February 2021 and November 2022. SMH performance varied widely as a function of both scenario validity and model calibration. Scenario assumptions were periodically invalidated by the arrival of unanticipated SARS-CoV-2 variants, but SMH still provided projections on average 22 weeks before changes in assumptions (such as virus transmissibility) invalidated scenarios and their corresponding projections. During these periods, before emergence of a novel variant, a linear opinion pool ensemble of contributed models was consistently more reliable than any single model, and projection interval coverage was near target levels for the most plausible scenarios (e.g., 79% coverage for 95% projection interval). SMH projections were used operationally to guide planning and policy at different stages of the pandemic, illustrating the value of the hub approach for long-term scenario projections.

15.
Lancet Reg Health Am ; 17: 100398, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36437905

RESUMO

Background: The COVID-19 Scenario Modeling Hub convened nine modeling teams to project the impact of expanding SARS-CoV-2 vaccination to children aged 5-11 years on COVID-19 burden and resilience against variant strains. Methods: Teams contributed state- and national-level weekly projections of cases, hospitalizations, and deaths in the United States from September 12, 2021 to March 12, 2022. Four scenarios covered all combinations of 1) vaccination (or not) of children aged 5-11 years (starting November 1, 2021), and 2) emergence (or not) of a variant more transmissible than the Delta variant (emerging November 15, 2021). Individual team projections were linearly pooled. The effect of childhood vaccination on overall and age-specific outcomes was estimated using meta-analyses. Findings: Assuming that a new variant would not emerge, all-age COVID-19 outcomes were projected to decrease nationally through mid-March 2022. In this setting, vaccination of children 5-11 years old was associated with reductions in projections for all-age cumulative cases (7.2%, mean incidence ratio [IR] 0.928, 95% confidence interval [CI] 0.880-0.977), hospitalizations (8.7%, mean IR 0.913, 95% CI 0.834-0.992), and deaths (9.2%, mean IR 0.908, 95% CI 0.797-1.020) compared with scenarios without childhood vaccination. Vaccine benefits increased for scenarios including a hypothesized more transmissible variant, assuming similar vaccine effectiveness. Projected relative reductions in cumulative outcomes were larger for children than for the entire population. State-level variation was observed. Interpretation: Given the scenario assumptions (defined before the emergence of Omicron), expanding vaccination to children 5-11 years old would provide measurable direct benefits, as well as indirect benefits to the all-age U.S. population, including resilience to more transmissible variants. Funding: Various (see acknowledgments).

16.
Nat Commun ; 14(1): 7260, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37985664

RESUMO

Our ability to forecast epidemics far into the future is constrained by the many complexities of disease systems. Realistic longer-term projections may, however, be possible under well-defined scenarios that specify the future state of critical epidemic drivers. Since December 2020, the U.S. COVID-19 Scenario Modeling Hub (SMH) has convened multiple modeling teams to make months ahead projections of SARS-CoV-2 burden, totaling nearly 1.8 million national and state-level projections. Here, we find SMH performance varied widely as a function of both scenario validity and model calibration. We show scenarios remained close to reality for 22 weeks on average before the arrival of unanticipated SARS-CoV-2 variants invalidated key assumptions. An ensemble of participating models that preserved variation between models (using the linear opinion pool method) was consistently more reliable than any single model in periods of valid scenario assumptions, while projection interval coverage was near target levels. SMH projections were used to guide pandemic response, illustrating the value of collaborative hubs for longer-term scenario projections.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias/prevenção & controle , SARS-CoV-2 , Incerteza
17.
Mol Plant Microbe Interact ; 25(4): 481-95, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22112214

RESUMO

Agrobacterium tumefaciens-mediated transformation (ATMT) was used to generate an insertional mutant library of the gray mold fungus Botrytis cinerea. From a total of 2,367 transformants, 68 mutants showing significant reduction in virulence on tomato and bean plants were analyzed in detail. As reported for other fungal ATMT libraries, integrations were mostly single copy, occurred preferentially in noncoding (regulatory) regions, and were frequently accompanied by small deletions of the target sequences and loss of parts of the border sequence. Two T-DNA integration events that were found to be linked to virulence were characterized in more detail: a catalytic subunit of a PP2A serine/threonine protein phosphatase (BcPP2Ac) and the SPT3 subunit of a Spt-Ada-Gcn5-acetyltransferase (SAGA-like) transcriptional regulator complex. Gene replacement and silencing approaches revealed that both Bcpp2Ac and SPT3 are crucial for virulence, growth, and differentiation as well as for resistance to H(2)O(2) in B. cinerea.


Assuntos
Botrytis/genética , Botrytis/metabolismo , DNA Bacteriano/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Fatores de Transcrição/metabolismo , Botrytis/patogenicidade , DNA Bacteriano/genética , Regulação Fúngica da Expressão Gênica/fisiologia , Biblioteca Gênica , Inativação Gênica , Mutagênese Insercional , Phaseolus/microbiologia , Fosfoproteínas Fosfatases/genética , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição/genética , Virulência
18.
Theor Appl Genet ; 124(7): 1283-94, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22274764

RESUMO

Leaf rust and stripe rust are important diseases of wheat world-wide and deployment of cultivars with genetic resistance is an effective and environmentally sound control method. The use of minor, additive genes conferring adult plant resistance (APR) has been shown to provide resistance that is durable. The wheat cultivar 'Pastor' originated from the CIMMYT breeding program that focuses on minor gene-based APR to both diseases by selecting and advancing generations alternately under leaf rust and stripe rust pressures. As a consequence, Pastor has good resistance to both rusts and was used as the resistant parent to develop a mapping population by crossing with the susceptible 'Avocet'. All 148 F(5) recombinant inbred lines were evaluated under artificially inoculated epidemic environments for leaf rust (3 environments) and stripe rust (4 environments, 2 of which represent two evaluation dates in final year due to the late build-up of a new race virulent to Yr31) in Mexico. Map construction and QTL analysis were completed with 223 polymorphic markers on 84 randomly selected lines in the population. Pastor contributed Yr31, a moderately effective race-specific gene for stripe rust resistance, which was overcome during this study, and this was clearly shown in the statistical analysis. Linked or pleiotropic chromosomal regions contributing to resistance against both pathogens included Lr46/Yr29 on 1BL, the Yr31 region on 2BS, and additional minor genes on 5A, 6B and 7BL. Other minor genes for leaf rust resistance were located on 1B, 2A and 2D and for stripe rust on 1AL, 1B, 3A, 3B, 4D, 6A, 7AS and 7AL. The 1AL, 1BS and 7AL QTLs are in regions that were not identified previously as having QTLs for stripe rust resistance. The development of uniform and severe epidemics facilitated excellent phenotyping, and when combined with multi-environment analysis, resulted in the relatively large number of QTLs identified in this study.


Assuntos
Doenças das Plantas/imunologia , Locos de Características Quantitativas , Triticum/genética , Basidiomycota/patogenicidade , Cruzamento , Cruzamentos Genéticos , Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/microbiologia , Triticum/imunologia , Triticum/microbiologia
19.
Acta Ortop Mex ; 36(6): 352-358, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-37669654

RESUMO

Cross-sectional-retrospective study with 120 anteroposterior pelvic radiographs. Eight measurements were taken by three raters in two times to calculate the morphological-cortical (MCI), cortico-metaphyseal (CMI), and cortico-diaphysaire (CDI) indices. Intra/interobserver reproducibility was evaluated with the Bland-Altman method, and hip fracture occurrence was predicted by comparing cut-off points between raters maximizing sensitivity/specificity. The proportion of measurements outside ± 2 SD was similar for diameters/corticals (~5%), but exceeded 1 mm in some corticals, representing 10-20% of distances < 1 cm. Cut-off points fluctuated between 2.45 and 2.53 for MCI (3% difference), between 0.37 and 0.41 for CMI (12% difference), and between 0.23 and 0.33 for CDI (44% difference).


Estudio transversal-retrospectivo con 120 radiografías pélvicas anteroposteriores. Se tomaron ocho mediciones por tres evaluadores en dos tiempos para calcular índices morfológico cortical (IMC), corticometafisario (ICM) y corticodiafisario (ICD). Se evaluó la reproducibilidad intra e interobservador con el método de Bland-Altman y se predijo la ocurrencia de fracturas comparando puntos de corte entre evaluadores maximizando sensibilidad/especificidad. La proporción de medidas fuera de ± 2 DE fue similar para diámetros/corticales (~5%), pero superó 1 mm en algunas corticales, representando 10-20% de distancias < 1 cm. El punto de corte fluctuó de 2.45 a 2.53 para IMC (3% diferencia), de 0.37 a 0.41 para ICD (12%) y de 0.23 a 0.33 para ICM (44%).


Assuntos
Fêmur , Fraturas do Quadril , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Estudos Transversais , Fraturas do Quadril/diagnóstico por imagem
20.
Acta Ortop Mex ; 36(4): 216-222, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-36977640

RESUMO

INTRODUCTION: distal radius fractures are the most common in upper extremities. Therefore, it is important to standardize radiographic measures for their surgical approach. This study assessed the intra/interobserver reproducibility of radiographic parameters associated with surgical success of distal radius fractures. MATERIAL AND METHODS: retrospective cross-sectional design of secondary data extracted from clinical records. Posteroanterior and lateral X-rays of 112 distal radius fractures were assessed by two trauma specialists standardized in the measurements required to compute five parameters indicative of postoperative success: radial height, radial inclination, volar tilt, ulnar variance, and articular stepoff. The reproducibility of distances and angles was evaluated using the Bland-Altman method, calculating the mean of the difference between measurements, the range at ± 2 SD, and the proportion of measurements outside ± 2 SD. Postoperative success was also compared between patients with and without obesity according to the mean of the two measures made by each evaluator. RESULTS: evaluator 1 had the largest intra-observer difference in radial height (0.16 mm) and the largest proportion outside ± 2 SD in ulnar variance (8.1%); evaluator 2 had the largest difference in volar tilt (1.92o) and the highest proportion in radial inclination (10.7%). The largest inter-observer difference was for ulnar variance (1.02 mm) and the largest proportion outside ± 2 SD. for radial height (5.4%). Radial tilt had the largest difference (1.41o) with 4.5% of measurements outside ± 2 SD. Ulnar variance and volar tilt had the largest difference in postoperative success between evaluators, especially in patients with obesity. CONCLUSION: improving the radiographic quality and standardizing the measurements results in more reproducible indicators.


INTRODUCCIÓN: las fracturas del radio distal son las más comunes en extremidades superiores. Estandarizar las mediciones radiográficas para su abordaje quirúrgico es importante. Este estudio midió la reproducibilidad intra/interobservador de parámetros radiográficos asociados al éxito quirúrgico en estas fracturas. MATERIAL Y MÉTODOS: diseño transversal retrospectivo con datos secundarios de expedientes clínicos. Se evaluaron radiografías de 112 fracturas en planos posteroanterior y lateral por dos traumatólogos estandarizados en toma de mediciones para calcular cinco parámetros indicativos de éxito postquirúrgico: altura radial, inclinación radial, inclinación volar, varianza cubital y escalón articular. La reproducibilidad de distancias y ángulos se evaluó con el método de Bland-Altman calculando: diferencia media entre mediciones, rango a ± 2 DE y proporción de mediciones fuera de ± 2 DE. El éxito postquirúrgico se comparó en pacientes con/sin obesidad según la media de las dos mediciones de cada evaluador. RESULTADOS: el evaluador 1 tuvo la mayor diferencia intraobservador en altura radial (0.16 mm) y la mayor proporción fuera de ± 2 DE en varianza cubital (8.1%); el evaluador 2 tuvo la mayor diferencia en inclinación volar (1.92o) y la mayor proporción en inclinación radial (10.7%). La mayor diferencia interobservador fue en varianza cubital (1.02 mm) y la mayor proporción fuera de ± 2 DE en altura radial (5.4%). La inclinación radial tuvo la mayor diferencia (1.41o) con 4.5% de mediciones fuera de ± 2 DE. La varianza cubital y la inclinación volar tuvieron la mayor diferencia de éxito postquirúrgico entre evaluadores, sobre todo en pacientes con obesidad. CONCLUSIÓN: mejorar la calidad radiográfica y estandarizar las mediciones resulta en indicadores más reproducibles.


Assuntos
Fraturas do Rádio , Fraturas do Punho , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Estudos Transversais , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Rádio (Anatomia) , Fixação Interna de Fraturas/métodos , Placas Ósseas , Amplitude de Movimento Articular , Resultado do Tratamento
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