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1.
Zhonghua Yi Xue Za Zhi ; 104(11): 850-856, 2024 Mar 19.
Artigo em Chinês | MEDLINE | ID: mdl-38462361

RESUMO

Objective: To evaluate the risk prediction and assessment function of HLA-DPB1 T-cell epitope (TCE) model and expression model in human leukocyte antigen (HLA)-matched unrelated hematopoietic stem cell transplantation (MUD-HSCT) with HLA-DPB1 mismatching. Methods: A total of 364 (182 pairs) potential MUD-HSCT donors and recipients confirmed by HLA high-resolution typing in Shaanxi Blood Center from 2016 to 2019 were analyzed retrospectively. Of the 182 recipients, there were 121 males and 61 females with an average age of (26.3±14.2) years. Of the 182 donors, there were 148 males and 34 females with an average age of (33.7±7.5) years. Polymerase chain reaction-sequence-based typing (PCR-SBT), next-generation sequencing (NGS) and polymerase chain reaction-sequence specific oligonucleotide probe (PCR-SSO) based on LABScan®3D platform were used for high-resolution typing of HLA-A, B, C, DRB1, DQB1, DPB1 gene, and PCR-SBT was used for single nucleotide polymorphism (SNP) typing. TCE model and expression model were used to predict and evaluate the HLA-DPB1 mismatch pattern and acute graft-versus-host-disease (aGVHD) risk. Results: A total of 26 HLA-DPB1 alleles and their 3'-UTR rs9277534 SNP genotypes were detected in this study population, and two new alleles HLA-DPB1*1052∶01 and HLA-DPB1*1119∶01 were found and officially named. The overall mismatch rate of HLA-DPB1 in MUD-HSCT donors and recipients was 90.66% (165/182). In TCE model, the HLA-DPB1 mismatch rates of permissible mismatch (PM) and non-permissible mismatch (non-PM) were 47.80% (87/182) and 42.86% (78/182), respectively. The non-PM in GvH direction was 13.73% (25/182), and which in HvG direction was 29.12% (53/182). A total of 73 pairs of donors and recipients in TCE model met the evaluation criteria of expression model. Among of TCE PM group, recipient DP5 mismatches accounted for 34.25% (25/73) were predicted as aGVHD high risk according to expression model. For the TCE non-PM group, both the recipient DP2 mismatches of 6.85% (5/73) and recipient DP5 mismatches of 10.86% (8/73) were predicted to be at high risk for aGVHD. Risk prediction by TCE model and expression model was 27.27% concordant and 16.97% unconcordant. Conclusions: TCE model and expression model are effective tools to predict aGVHD risk of MUD-HSCT. Comprehensive application of the two models is helpful to the hierarchical assessment of HSCT risk.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Masculino , Feminino , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Epitopos de Linfócito T/genética , Estudos Retrospectivos , Cadeias beta de HLA-DP/genética , Doadores não Relacionados , Doença Enxerto-Hospedeiro/genética
2.
Artigo em Chinês | MEDLINE | ID: mdl-33535336

RESUMO

Objective: To explore the risk factors of acute renal injury (AKI) in exertional heat radiation disease (EHS) . Methods: In november 2019, the clinical data of 69 EHS patients admitted from July 2015 to September 2019 were reviewed. The general data, laboratory indexes, Glasgow score (GCS) at admission, 24-hour acute physiology and chronic health score Ⅱ (APACHE Ⅱ) , exposure time rate and physical labor intensity were collected. According to the occurrence of AKI, the patients were divided into AKI group and non-AKI group, 31 and 38 in each group. The differences of general data and laboratory indexes between the two groups were compared, and the t and Mann-Whitney U test were used to compare the two groups. The enumeration data are expressed by examples and constituent ratio (%) . Independent sample χ(2) test is used for inter-group comparison, and multiple test is used for multi-sample comparison. The correlation was analyzed by linear regression. Risk factors were analyzed by Logistic regression analysis. Results: At discharge, 31 of 69 EHS patients developed AKI. Compared with the non-AKI group, the heart rate, white blood cell count, lactic acid, D-dimer and myoglobin were higher; MAP, platelet count and PH were lower in the AKI group. The difference was statistically significant (P<0.05) . APACHE Ⅱ score, core temperature, time to drop to 38.5 ℃, contact time rate, platelet count, pH, lactic acid, D-dimer and myoglobin were all correlated with creatinine (r=0.57, 0.42, 0.80, 0.78, 0.57, 0.43, 0.51, 0.55, 0.79) . APACHE Ⅱ score, time to drop to 38.5C, Lac and MYO are the risk factors of AKI in EHS patients. Multivariate Logistic regression analysis showed that the time required to drop to 38.5C was an independent risk factor for the occurrence of AKI. Conclusion: AKI is a serious complication of EHS. EHS complicated with AKI, should be identified early and effective intervention measures should be taken.


Assuntos
Injúria Renal Aguda , Golpe de Calor , APACHE , Golpe de Calor/complicações , Humanos , Prognóstico , Estudos Retrospectivos , Fatores de Risco
3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 52(2): 221-226, 2020 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-32306002

RESUMO

OBJECTIVE: To analyze the subcellular localization of GTPase of immunity-associated protein 2 (GIMAP2) for the further functional study. METHODS: In the study, we first obtained the protein sequences of GTPase of immunity-associated protein 2 (GIMAP2) from National Center for Biotechnology Information (NCBI) database, and then performed a prediction analysis of its transmembrane structure, nuclear localization signal (NLS), nuclear export signal (NES) and subcellular localization through bioinformatics online tools. GIMAP2 gene amplified by PCR was inserted into the expression vector pQCXIP-mCherry-N1 and positive clones were selected by ampicillin resistance. After using methods to extract and purify, the sequenced recombinant plasmid pQCXIP-GIMAP2-mCherry, together with the retroviral packaging plasmids VSVG and Gag/pol, was transferred into HEK293FT cells by liposomes for virus packaging. The virus supernatant was collected 48 h after transfection and directly infected the human breast cancer cell line MDA-MB-436. Immunofluorescence staining was constructed to detect the localization of endogenous and exogenous GIMAP2 in MDA-MB-436 cells. Meanwhile, green fluorescent chemical dyes were used to label mitochondria, endoplasmic reticulum, and lipid droplets in living MDA-MB-436 cells stably expressing the GIMAP2-mCherry fusion protein. Images for the three dye-labeled organelles and GIMAP2-mCherry fusion protein were captured by super-resolution microscope N-SIM. RESULTS: Bioinformatics analysis data showed that GIMAP2 protein composed of 337 amino acids might contain two transmembrane helix (TM) structures at the carboxyl terminus, of which TMs were estimated to contain 40-41 expected amino acids, followed by the residual protein structures toward the cytoplasmic side. NES was located at the 279-281 amino acids of the carboxyl terminus whereas NLS was not found. GIMAP2 might locate in the lumen of the endoplasmic reticulum. Sequencing results indicated that the expression vector pQCXIP-GIMAP2-mCherry was successfully constructed. Fluorescent staining confirmed that GIMAP2-mCherry fusion protein, co-localized well with endogenous GIMAP2, expressed successfully in the endoplasmic reticulum and on the surface of lipid droplets in MDA-MB-436 cells. CONCLUSION: GIMAP2 localizes in the endoplasmic reticulum and on the surface of LDs, suggesting potential involvement of GIMAP2 in lipid metabolism.


Assuntos
Sinais de Localização Nuclear , Sequência de Aminoácidos , Citoplasma , GTP Fosfo-Hidrolases , Humanos , Proteínas de Membrana , Sinais de Exportação Nuclear , Proteínas Recombinantes de Fusão , Transfecção
4.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(10): 831-836, 2020 Oct 24.
Artigo em Chinês | MEDLINE | ID: mdl-33076619

RESUMO

Objective: To investigate the clinical characteristics and gene mutation, and analyze the association between genotype and phenotype of hereditary protein S deficiency in a Chinese pedigree. Methods: Hereditary protein S deficiency was diagnosed in January 2016 in our hospital. A total of 26 family members were surveyed in this study. Blood samples and clinical data were collected from them, and mutations were identified by Sanger sequencing. Pathogenicity of gene mutations was predicted by protein function prediction software including SIFT, PolyPhen_2, nsSNPAnalyzer and MutPred2. Swiss Model (https://swissmodel.expasy.org/) was used to perform homology modeling of the tertiary structure of the protein S wild-type and mutant-type, and observe the impact of gene mutation on the tertiary structure of the protein. Results: Four out of 26 family members of 4 generations were clinically diagnosed with hereditary protein S deficiency. The proband presented with recurrent pulmonary embolism and venous thromboembolism of the lower extremities, and her uncle and mother had a history of venous thromboembolism. Sequencing revealed a mutation in the c.200A>C gene in the second exon of the PROS1 gene of proband and part of her families (Ⅱ2, Ⅱ6, Ⅲ4, Ⅳ2). The prediction results of this gene mutation performed by SIFT, PolyPhen_2, nsSNPAnalyzer, MutPred2 were all harmful. The results of Swiss-Model homology modeling showed that the 67th amino acid was mutated from glutamic acid to alanine because of this gene mutation. Conclusion: A gene mutation cDNA (c. 200A>T) is identified in a Chinese pedigree with hereditary protein S deficiency. This gene mutation may reduce protein S activity, which may cause recurrent pulmonary embolism and venous thromboembolism of the patients.


Assuntos
Deficiência de Proteína S , Povo Asiático/genética , Éxons , Feminino , Humanos , Linhagem , Inquéritos e Questionários
5.
Artigo em Chinês | MEDLINE | ID: mdl-32629579

RESUMO

Objective: To evaluate the prognostic value of different critical care scoring systems in 28-day survival rate of patients with heat stroke. Methods: A retrospective analysis was conducted on the clinical data of 71 patients with heat stroke admitted to the department of emergency medicine of Beijing Luhe Hospital. Capital Medical University from July 2015 to September 2018. The general information and the worst values of vital signs and related pathophysiological indicators within 24 hours were collected and the sequential organ failure assessment (SOFA) , multiple organ dysfunction (MODS) , simplified acute physiological scoreⅡ (SAPS Ⅱ) and acute physiology and chronic health evaluationⅡ (APACHE Ⅱ) were calculated. The patients were divided into the survival group (n=45) and the non-survival group (n=26) according to 28-day prognosis, and the clinical data and scores of the two groups were compared.The ROC curve was drawn to analyze the evaluation value of each scoring system on the survival rate of patients at 28-day. Kaplan-Meier method was used to plot the survival curve of patients. Results: There were no significant differences in age, sex, vital signs and laboratory parameters between two groups (P>0.05) . In non-survival patients, SOFA, SAPS Ⅱ, APACHE Ⅱ scores were significantly elevated in the survival group (P<0.05) . ROC curve analysis showed that the area under ROC curve (AUC) of SOFA score for predicting 28-day survival rate was the highest, which was significantly higher than the APACHE Ⅱ, SAPS Ⅱ, MODS score. When the best cut-off value of SOFA score was 9.0, the sensitivity was 84.6%, and the specificity was 71.1%. Kaplan-Meier survival analysis showed that 28-day survival rate after hospital discharge in patients with SOFA score<9 (n=27) was significantly higher than that in patients with SOFA score ≥9.0 (χ(2)=1.0, P<0.01) . Conclusion: SOFA, APACHE Ⅱ, SAPS Ⅱ on admission have been proved to have good prognostic ability to predict 28-day prognosis in heat stroke patients. Among them, SOFA score system has more accurate prediction value.


Assuntos
Cuidados Críticos , Golpe de Calor/diagnóstico , APACHE , Humanos , Unidades de Terapia Intensiva , Prognóstico , Curva ROC , Estudos Retrospectivos
6.
Theor Appl Genet ; 132(6): 1677-1691, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30796480

RESUMO

KEY MESSAGE: This study determined the effects of growth stage and temperature on expression of high-temperature adult-plant resistance to stripe rust, mapped six QTL for durable resistance in winter wheat Skiles using a doubled haploid population, and selected breeding lines with different combinations of the QTL using marker-assisted selection. The winter wheat cultivar Skiles has a high level of high-temperature adult-plant (HTAP) resistance to stripe rust caused by Puccinia striiformis f. sp. tritici (Pst). The Skiles HTAP resistance was highly effective at the adult-plant stage even under low temperatures, but high temperatures induced earlier expression and increased levels of resistance. To map resistance genes, Skiles was crossed with the susceptible cultivar Avocet S and a doubled haploid (DH) population was developed. The DH population was tested in fields at Pullman, WA, in 2016, 2017 and 2018, Mount Vernon, WA, in 2017 and 2018 under natural infection, and an environmentally controlled greenhouse at the adult-plant stage with the currently predominant race PSTv-37. The population was genotyped using the 90 K Illumina iSelect wheat SNP chip and selected SSR markers on specific chromosomes. In total, 2526 polymorphic markers were used for QTL mapping and six QTL were detected. Two of the six QTL had major effects across all environments, with one mapped on chromosome 3BS, explaining up to 28.2% of the phenotypic variation and the other on chromosome 4BL, explaining up to 41.8%. Minor QTL were mapped on chromosomes 1BL, 5AL, 6B and 7DL. Genotyping 140 wheat cultivars from the US Pacific Northwest revealed high polymorphism of markers for five of the QTL, and five highly resistant lines with the five QTL were selected from Skiles-derived breeding lines using the markers. This study demonstrated that multiple QTL with mostly additive effects contributed to the high-level HTAP resistance in Skiles.


Assuntos
Basidiomycota/fisiologia , Cromossomos de Plantas/genética , Resistência à Doença/genética , Doenças das Plantas/genética , Locos de Características Quantitativas , Estações do Ano , Triticum/genética , Mapeamento Cromossômico , Genótipo , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Temperatura , Triticum/microbiologia , Estados Unidos
7.
Osteoporos Int ; 29(4): 973-985, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29383389

RESUMO

Is gout a risk factor for future osteoporosis? This large population-based study comprising two matched groups of individuals with and without gout demonstrates that patients with gout have a 20% increase in the risk of developing osteoporosis in future through an 8-year follow-up. INTRODUCTION: To examine if gout is associated with an increased risk of osteoporosis. METHODS: We conducted a nationwide population-based retrospective matched-cohort study. Two matched cohorts (n = 36,458 with gout and 71,602 without gout) assembled and recruited from the Longitudinal Health Insurance Dataset containing 1 million subjects. Exclusion criteria were missing data, age < 20 years, short follow-up period, and pre-existing osteoporosis. Both cohorts were followed up until incident osteoporosis, death, or the end of the study. Person-year data and incidence rates were evaluated. A multivariable Cox model was used to derive an adjusted hazard ratio (aHR) after controlling for socioeconomic proxy, geographical difference, glucocorticoid and allopurinol exposure, various prespecified medical conditions, and comorbidities. RESULTS: Men comprised 72.8% of the cohorts. With a follow-up of 183,729 and 359,900 person-years for the gout and non-gout cohorts, 517 and 811 incidents of osteoporosis occurred, respectively, after excluding osteoporosis incidents in the first 3 years of follow-up. The cumulative incidence of osteoporosis was statistically higher in the gout cohort than in the non-gout cohort, at 3.3 versus 2.1% (P = 0.0036, log-rank). Our Cox model showed a 1.2-fold increase in the incidence of osteoporosis in the gout cohort, with an aHR of 1.2 (95% confidence interval, 1.06-1.35). CONCLUSIONS: This first population-based epidemiologic study supports the hypothesis that compared with individuals without gout; those with gout have a modest increase in the risk of developing osteoporosis in future.


Assuntos
Gota/epidemiologia , Osteoporose/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Gota/complicações , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Osteoporose/etiologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/etiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Taiwan/epidemiologia , Adulto Jovem
8.
Theor Appl Genet ; 131(9): 1835-1849, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29797034

RESUMO

KEY MESSAGE: Wheat cultivar Madsen has a new gene on the short arm of chromosome 1A and two QTL for all-stage resistance and three QTL for high-temperature adult-plant resistance that in combination confer high-level, durable resistance to stripe rust. Wheat cultivar Madsen has maintained a high-level resistance to stripe rust over 30 years. To map quantitative trait loci (QTL) underlying the high-level, durable resistance, 156 recombinant inbred lines (RILs) developed from cross Avocet S × Madsen were phenotyped with selected races of Puccinia striiformis f. sp. tritici in the greenhouse seedling tests, and in naturally infected fields during 2015-2017. The RILs were genotyped by SSR and SNP markers from genotyping by sequencing and the 90 K wheat SNP chip. Three QTL for all-stage resistance were mapped on chromosomes 1AS, 1BS and 2AS, and two QTL for high-temperature adult-plant (HTAP) resistance were mapped on 3BS and 6BS. The most effective QTL on 2AS, explaining 8.97-23.10% of the phenotypic variation in seedling tests and 8.60-71.23% in field tests, contained Yr17 for all-stage resistance and an additional gene for HTAP resistance. The 6BS QTL, detected in all field tests, was identified as Yr78. The 1AS QTL, conferring all-stage resistance, was identified as a new gene, which explained 20.45 and 30.23% of variation in resistance to races PSTv-37 and PSTv-40, respectively, and contributed significantly to field resistance at Pullman in 2015-2017, but was not detected at Mount Vernon. The interactions among QTL were mostly additive, and RILs with all five QTL had the highest level of resistance in the field, similar to Madsen. Genotyping 148 US Pacific Northwest wheat cultivars with markers for the 1AS, 2AS and 6BS QTL validated the genes and markers, and indicated their usefulness for marker-assisted selection.


Assuntos
Resistência à Doença/genética , Temperatura Alta , Doenças das Plantas/genética , Locos de Características Quantitativas , Triticum/genética , Basidiomycota , Mapeamento Cromossômico , Ligação Genética , Marcadores Genéticos , Genótipo , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Triticum/microbiologia
9.
Phytopathology ; 106(10): 1186-1193, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27050567

RESUMO

Tyee, one of the wheat cultivars used to differentiate races of Puccinia striiformis f. sp. tritici in the United States, was identified to have a single gene for all-stage resistance, tentatively named YrTye. To map the gene, Tyee was crossed with 'Avocet Susceptible' (AvS). Genetic analysis of the F1, F2, F2:3, and BC1 progenies confirmed a single dominant gene for resistance to race PSTv-37 that is avirulent to YrTye. A mapping population of 135 F2 plants was phenotyped with PSTv-37 and the derived F2:3 lines were tested with races PSTv-37, PSTv-40, and PSTv-79. The F2 mapping population was genotyped with simple sequence repeat (SSR) markers. A genetic map comprising 13 SSR markers located YrTye in chromosome 3AS flanked distally by SSR marker wmc11 and proximally by wmc532 at 2.6 and 3.4 cM, respectively. Amplification of Chinese Spring 3A deletion lines placed the gene in the distal bin 3AS4-0.45 to 1.00. Because YrTye is different from all formally named Yr genes in chromosomal location, we permanently name the gene Yr76. A near-isogenic line of spring common wheat was developed and selected by testing F3 lines derived from a AvS*4/Tyee cross with Tyee-avirulent and virulent races and the flanking markers. The specific SSR alleles flanking Yr76 were validated using cultivars and breeding lines with and without the gene, and showed high polymorphisms. The specificity of Yr76 is useful in differentiating P. striiformis f. sp. tritici races, and its tightly linked markers will be useful in developing resistant cultivars when combining the gene with other genes for resistance to stripe rust.


Assuntos
Basidiomycota/fisiologia , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Resistência à Doença/genética , Doenças das Plantas/imunologia , Triticum/genética , Alelos , Cruzamento , Genótipo , Repetições de Microssatélites/genética , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo Genético/genética , Triticum/imunologia , Triticum/microbiologia
10.
Phytopathology ; 105(9): 1206-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25871858

RESUMO

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is an important disease of wheat worldwide. Resistance is the best way to control the disease. YrSP, a gene originally from 'Spaldings Prolific' wheat and providing resistance to a broad spectrum of races, is used for differentiating P. striiformis f. sp. tritici races but its chromosomal location is not clear. To map YrSP, a near-isogenic line (AvSYrSPNIL) was backcrossed to the recurrent parent, Avocet S. Genetic analysis of the BC7F1, BC8, BC7F2, and BC7F3 progenies confirmed a single dominant gene for resistance. In total, 182 BC7F2 plants and their derived BC7F3 lines were phenotyped with an avirulent P. striiformis f. sp. tritici race and genotyped with simple-sequence repeat (SSR), single-nucleotide polymorphism (SNP), and sequence-tagged site (STS) markers. A linkage map was constructed with 3 SSR, 17 SNP, and 3 STS markers covering 23.3 centimorgans (cM). Markers IWA638 and dp269 were 0.6 cM proximal and 1.5 cM distal, respectively, to YrSP. The gene was mapped in chromosome bin 2BL-C-0.5, physically within the proximal 50% of the chromosome 2BL arm. Allelism tests based on F2 phenotypes indicated that YrSP is closely linked to but not allelic with genes Yr5, Yr7, Yr43, Yr44, and Yr53. Infection type data from tests with 10 historical and currently predominant P. striiformis f. sp. tritici races in the United States also demonstrated differences in specificity between YrSP and the other genes. The specificity of YrSP is useful in differentiating P. striiformis f. sp. tritici races and studying the plant-pathogen interactions, and the information of chromosomal location of the gene and its tightly linked markers should be useful in developing resistant cultivars when combined with other genes for resistance to stripe rust.


Assuntos
Basidiomycota/fisiologia , Cromossomos de Plantas/genética , Resistência à Doença , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Triticum/genética , Alelos , Mapeamento Cromossômico , Cruzamentos Genéticos , Ligação Genética , Marcadores Genéticos/genética , Genótipo , Repetições de Microssatélites/genética , Fenótipo , Doenças das Plantas/microbiologia , Sitios de Sequências Rotuladas , Triticum/imunologia , Triticum/microbiologia
11.
Plant Dis ; 99(11): 1500-1506, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30695954

RESUMO

Sexual reproduction of the stem rust pathogen, Puccinia graminis f. sp. tritici (Pgt), on barberry (Berberis vulgaris) has been shown to provide initial inoculum for the development of the disease on wheat and barley and also generate diverse races of the pathogen. However, in our previous study, the stripe rust pathogen, P. striiformis f. sp. tritici (Pst), was not found on barberry in the U. S. Pacific Northwest. To determine why Pgt is able to infect the alternate host, while Pst cannot under the natural conditions, the viabilities of teliospores of both Pgt and Pst were investigated from 2011 to 2014 by determining the germination rates using telial samples collected periodically from wheat fields. Teliospores of Pst usually produced in July were physically degraded during winter, and their germination rate decreased from 50 to 90% in August to less than 1% in the following March and no germination after May. In contrast, Pgt teliospores usually produced in July and August remained physically intact and physiologically dormant, and could not germinate until February. Germination of Pgt teliospores gradually increased to 90% in May, at which time young leaves of barberry were susceptible to infection. In addition, a time-series experiment was conducted for inoculation of barberry plants with Pst teliospores. The results showed that Pst teliospores need a minimum of 32 h continual dew-forming conditions to infect barberry, and infection reaches a peak after incubation of inoculated plants for 88 h. The lack of a prolonged period of leaf wetness conditions during the season of telial maturity effectively negates Pst infection of barberry plants in the Pacific Northwest.

12.
Plant Dis ; 99(11): 1507-1516, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30695965

RESUMO

Common barberry (Berberis vulgaris) is the alternate host of the wheat stem rust pathogen, Puccinia graminis f. sp. tritici, under natural conditions in the U.S. Pacific Northwest. Barberry was recently shown to be infected by basidiospores of the wheat stripe rust pathogen, Puccinia striiformis f. sp. tritici, under controlled conditions, but it is unclear if barberry plays any role in stripe rust epidemics under natural conditions. Aecial samples of Puccinia spp. collected from barberry plants in the Pacific Northwest from 2010 to 2013 were characterized to species by inoculation on wheat plants under controlled conditions and by molecular markers and sequences of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA. Inoculation of wheat plants with bulked aecia-bearing barberry samples resulted in most P. graminis f. sp. tritici uredia and some P. striiformis f. sp. tritici uredinia. Virulence tests demonstrated that the P. graminis f. sp. tritici isolates were sexually produced, whereas the P. striiformis f. sp. tritici isolates were clonal based on both virulence and simple sequence repeat marker tests, indicating urediniospores from wheat fields landing on barberry leaves as the possible source of P. striiformis f. sp. tritici inoculum. A method for simultaneously testing individual aecia for identifying of P. graminis f. sp. tritici and P. striiformis f. sp. tritici by pathogenicity and ITS markers. Using the method together with ITS sequencing, tested individual aecia were mostly P. graminis f. sp. tritici and occasionally some other formae speciales of P. graminis, but not P. striiformis. The results imply that barberry is essential for stem rust epidemics, but not for stripe rust under the natural conditions in the U.S. Pacific Northwest.

13.
Theor Appl Genet ; 127(4): 935-45, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24487945

RESUMO

KEY MESSAGE: This manuscript reports a new gene for non-race-specific resistance to stripe rust and molecular markers for incorporating it into wheat cultivars for control of the disease with durable resistance. Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most destructive wheat diseases worldwide. The spring wheat germplasm 'PI 178759' originating from Iraq showed effective resistance to stripe rust in field evaluations over 8 years in Washington state, USA. To map the resistance gene(s), PI 178759 was crossed with 'Avocet Susceptible', and the parents and 176 F2:3 lines were phenotyped in the fields under natural infection and in a greenhouse with selected races of P. striiformis f. sp. tritici. PI 178759 was identified to have high-temperature adult-plant (HTAP) resistance. Resistance gene analog polymorphism and simple sequence repeat techniques were used to identify molecular markers linked to the resistance gene and a chromosome region was mapped using a quantitative trait locus approach. One major gene was mapped to the long arm of chromosome 7B. Flanked by Xwgp5175 and Xbarc32 in a 2.1 cM region, the gene explained 31.8 and 54.7 % of the phenotypic variation in rAUDPC and IT, respectively. Based on genetic distances among markers and allelism tests, the HTAP resistance gene in PI 178759 is different from the previously reported Yr39, Yr52, YrZH84, and YrC591, also located on chromosome 7BL, and is therefore designated as Yr59. The gene and its flanking markers should be useful for developing wheat cultivars with durable resistance.


Assuntos
Basidiomycota/fisiologia , Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/genética , Sementes/genética , Temperatura , Triticum/genética , Triticum/microbiologia , Alelos , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Marcadores Genéticos , Padrões de Herança/genética , Repetições de Microssatélites/genética , Doenças das Plantas/microbiologia , Polimorfismo Genético , Locos de Características Quantitativas/genética , Plântula/genética , Plântula/microbiologia
14.
Theor Appl Genet ; 127(10): 2267-77, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25142874

RESUMO

KEY MESSAGE: This manuscript reports two new genes ( Yr64 and Yr65 ) for effective resistance to stripe rust and usefulness of their flanking SSR markers for marker-assisted selection. Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases of wheat worldwide and resistance is the best control strategy. Durum wheat accessions PI 331260 and PI 480016 were resistant to all tested Pst races. To transfer the resistance genes to common wheat and map them to wheat chromosomes, both accessions were crossed with the stripe rust-susceptible spring wheat 'Avocet S'. Resistant F3 plants with 42 chromosomes were selected cytologically and by rust phenotype. A single dominant gene for resistance was identified in segregating F4 lines from each cross. F6 populations for each cross were developed from single F5 plants and used for genetic mapping. Different genes from PI 331260 and PI 480016 were mapped to different loci in chromosome 1BS using simple sequence repeat markers. The gene from PI 331260 was flanked by Xgwm413 and Xgdm33 in bin 1BS9-0.84-1.06 at genetic distances of 3.5 and 2.0 cM; and the gene from PI 480016 was flanked by Xgwm18 and Xgwm11 in chromosome bin C-1BS10-0.50 at 1.2 and 2.1 cM, respectively. Chromosomal locations and race and allelism tests indicated that the two genes are different from previously reported stripe rust resistance genes, and therefore are named as Yr64 from PI 331260 and Yr65 from PI 480016. These genes and their flanking markers, and selected common wheat lines with the genes should be valuable for diversifying resistance genes used in breeding wheat cultivars with stripe rust resistance.


Assuntos
Mapeamento Cromossômico , Resistência à Doença/genética , Genes de Plantas , Triticum/genética , Basidiomycota , Cromossomos de Plantas , DNA de Plantas/genética , Genes Dominantes , Marcadores Genéticos , Repetições de Microssatélites , Fenótipo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Poliploidia , Triticum/microbiologia
15.
Theor Appl Genet ; 126(2): 523-33, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23090143

RESUMO

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most damaging diseases of wheat worldwide. It is essential to identify new genes for effective resistance against the disease. Durum wheat PI 480148, originally from Ethiopia, was resistant in all seedling tests with several predominant Pst races in the US under controlled greenhouse conditions and at multiple locations subject to natural infection for several years. To map the resistance gene(s) and to transfer it to common wheat, a cross was made between PI 480148 and susceptible common wheat genotype Avocet S (AvS). Resistant F(3) plants with 42 chromosomes were selected cytologically and by testing with Pst race PST-100. A total of 157 F(4) plants from a single F(3) plant with 2n = 42 tested with PST-100 segregated in a 3 resistant: 1 susceptible ratio, indicating that a single dominant gene from PI 480148 conferred resistance. Using the F(3:4) population and the resistance gene-analog polymorphism (RGAP) and simple sequence repeat (SSR) markers, the gene was mapped to the long arm of chromosome 2B. SSR marker Xwmc441 and RGAP marker XLRRrev/NLRRrev ( 350 ) flanked the resistance gene by 5.6 and 2.7 cM, respectively. The effective resistance of the gene to an Australian Pst isolate virulent to Yr5, which is also located on 2BL and confers resistance to all US Pst races, together with an allelism test of the two genes, indicated that the gene from PI 480148 is different from Yr5 and should be a new and useful gene for resistance to stripe rust. Resistant common wheat lines with plant types similar to AvS were selected for use in breeding programs.


Assuntos
Basidiomycota/fisiologia , Mapeamento Cromossômico , Resistência à Doença/genética , Genes de Plantas/genética , Doenças das Plantas/genética , Triticum/genética , Basidiomycota/patogenicidade , Cromossomos de Plantas/genética , Etiópia , Ligação Genética/genética , Imunidade Inata , Fenótipo , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Triticum/imunologia , Triticum/microbiologia
16.
Plant Dis ; 97(6): 839, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30722629

RESUMO

As the primary host of the stripe rust pathogen, Puccinia striiformis f. sp. tritici (Pst), wheat can be infected by both aeciospores and urediniospores, and later is the host that gives rise to urediniospores and teliospores. Barberry species (e.g., Berberis vulgaris) can be infected by basidiospores, produced from the teliospores of wheat plants, and later gives rise to pycniospores and aeciospores, which has been demonstrated through artificial inoculation (3). Oregon grape (Mahonia aquifolium), closely related to Berberis, is a native evergreen shrub that is also grown as an ornamental plant in the Pacific Northwest. To determine if M. aquifolium can also serve as an alternate host for Pst, we conducted artificial inoculations under controlled conditions. Seeds of M. aquifolium collected from Pullman, WA, were sown in pots filled with soil mixture, and plants were grown in a greenhouse under wheat-growing conditions (1). In the first experiment, conducted in May to June 2011, the inoculum was telia collected from artificially inoculated wheat cv. Avocet S with urediniospores of isolate 09-134 (race PST-127) from the greenhouse. In the second experiment, conducted in July to August 2011, the inoculum was telia collected from naturally infected wheat cv. Nugaines with urediniospores from isolate 11-292 (race PST-127) from an experimental field near Pullman. For each experiment, mature teliospores of 60 telia from a single wheat plant were suspended in 1.0 ml of distilled water and inoculated with a fine paint brush onto the leaves of seven or eight 10- to 15-day-old plants of M. aquifolium. Plants were incubated initially in a dew chamber at 10°C for 72 h in darkness, then transferred to a growth chamber with a diurnal temperature cycle of 10 to 24°C and a 16 h light/8 h dark cycle (1). Reddish pycnia with nectar appeared on adaxial surfaces of inoculated leaves at 12 days post-inoculation (DPI), and reddish aecia were produced on the baxial surface at 16 DPI. All 15 M. aquifolium leaves of the 15 plants inoculated with teliospores produced pycnia and aecia. Seedlings of Nugaines and Avocet S, wheat cultivars that are susceptible to all Pst races (1), were then inoculated with a water suspension of aeciospores of 30 aecia collected from the M. aquifolium plants. Wheat plants were incubated as described above for M. aquifolium. Uredinia appeared at 15 DPI, and telia were produced after an additional 15 days. From these uredinia that formed on inoculated wheat, a total of 30 single-uredinium isolates were obtained using the standard procedure (1). Virulence tests were carried out on 20 wheat differentials for 10 randomly selected urediniospore isolates, revealing six virulence patterns. When tested with four selected Pst SSR markers (PstP001, PstP003, PstP005, PstP029) (2) and compared to other race PST-127 isolates, all 10 progeny isolates were homozygous, as were the parental isolates (09-134, 11-292). The virulence tests and marker genotypes verified that the urediniospore isolates resulted from infection by aecia, produced by parental isolate 09-134 through its sexual cycle on M. aquifolium. The study exhibited the completed sexual lifecycle of Pst through the five spore stages on wheat and M. aquifolium in a controlled setting, and suggests that under appropriate weather conditions, M. aquifolium may serve as an alternate host for Pst. Due to the wide distribution of M. aquifolium, further studies are needed to determine if the species can be infected by Pst under natural conditions. References: (1) X. M. Chen et al. Can. J. Plant Pathol. 32:315, 2010. (2) P. Cheng et al. Mol. Ecol. Resour. 12:779, 2012. (3) Y. Jin et al. Phytopathology 100:432, 2010.

17.
Theor Appl Genet ; 125(5): 847-57, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22562146

RESUMO

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most destructive diseases of wheat worldwide. Resistance is the best approach to control the disease. High-temperature adult-plant (HTAP) stripe rust resistance has proven to be race non-specific and durable. However, genes conferring high-levels of HTAP resistance are limited in number and new genes are urgently needed for breeding programs to develop cultivars with durable high-level resistance to stripe rust. Spring wheat germplasm PI 183527 showed a high-level of HTAP resistance against stripe rust in our germplasm evaluations over several years. To elucidate the genetic basis of resistance, we crossed PI 183527 and susceptible wheat line Avocet S. Adult plants of parents, F(1), F(2) and F(2:3) progeny were tested with selected races under the controlled greenhouse conditions and in fields under natural infection. PI 183527 has a single dominant gene conferring HTAP resistance. Resistance gene analog polymorphism (RGAP) and simple sequence repeat (SSR) markers in combination with bulked segregant analysis (BSA) were used to identify markers linked to the resistance gene. A linkage map consisting of 4 RGAP and 7 SSR markers was constructed for the resistance gene using data from 175 F(2) plants and their derived F(2:3) lines. Amplification of nulli-tetrasomic, ditelosomic and deletion lines of Chinese Spring with three RGAP markers mapped the gene to the distal region (0.86-1.0) of chromosome 7BL. The molecular map spanned a genetic distance of 27.3 cM, and the resistance gene was narrowed to a 2.3-cM interval flanked by markers Xbarc182 and Xwgp5258. The polymorphism rates of the flanking markers in 74 wheat lines were 74 and 30 %, respectively; and the two markers in combination could distinguish the alleles at the resistance locus in 82 % of tested genotypes. To determine the genetic relationship between this resistance gene and Yr39, a gene also on 7BL conferring HTAP resistance in Alpowa, a cross was made between PI 183527 and Alpowa. F(2) segregation indicated that the genes were 36.5 ± 6.75 cM apart. The gene in PI 183527 was therefore designed as Yr52. This new gene and flanking markers should be useful in developing wheat cultivars with high-level and possible durable resistance to stripe rust.


Assuntos
Basidiomycota/genética , Cromossomos de Plantas/genética , Genes de Plantas/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Triticum/genética , Triticum/microbiologia , Basidiomycota/imunologia , Mapeamento Cromossômico , DNA de Plantas/genética , Ligação Genética , Marcadores Genéticos , Temperatura Alta , Imunidade Inata/genética , Desequilíbrio de Ligação , Doenças das Plantas/imunologia , Reação em Cadeia da Polimerase , Polimorfismo Genético , Estações do Ano , Triticum/imunologia
18.
Theor Appl Genet ; 122(1): 189-97, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20838759

RESUMO

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most destructive diseases of wheat worldwide. Growing resistant cultivars is the most effective approach to control the disease, but only a few genes confer effective all-stage resistance against the current populations of the pathogen worldwide. It is urgent to identify new genes for diversifying sources of resistance genes and for pyramiding genes for different types of resistance in order to achieve high levels of durable resistance for sustainable control of stripe rust. The common spring wheat genotype 'PI 181434', originally from Afghanistan, was resistant in all greenhouse and field tests in our previous studies. To identify the resistance gene(s) PI 181434 was crossed with susceptible genotype 'Avocet Susceptible'. Adult plants of 103 F(2) progeny were tested in the field under the natural infection of P. striiformis f. sp. tritici. Seedlings of the parents, F(2) and F(3) were tested with races PST-100 and PST-127 of the pathogen under controlled greenhouse conditions. The genetic study showed that PI 181434 has a single dominant gene conferring all-stage resistance. Resistance gene analog polymorphism (RGAP) and simple sequence repeat (SSR) techniques were used to identify molecular markers linked to the gene. A linkage map of 8 RGAP and 2 SSR markers was constructed for the gene using data from the 103 F(2) plants and their derived F(3) lines tested in the greenhouse. Amplification of the complete set of nulli-tetrasomic lines and selected ditelosomic lines of Chinese Spring with an RGAP marker and the two SSR markers mapped the gene on the long arm of chromosome 3D. Because it is the first gene for stripe rust resistance mapped on chromosome 3DL and different from all previously named Yr genes, the gene in PI 181434 was designated Yr45. Polymorphism rates of the two closest flanking markers, Xwgp115 and Xwgp118, in 45 wheat genotypes were 73.3 and 82.2%, respectively. Single nucleotide polymorphisms (SNPs) were identified in the eight wheat genotypes sharing both flanking markers. The RGAP markers and potential SNP markers should be useful in incorporating the gene into wheat cultivars and in pyramiding it with other genes for durable resistance.


Assuntos
Basidiomycota/fisiologia , Cromossomos de Plantas/genética , Genes de Plantas/genética , Imunidade Inata/genética , Doenças das Plantas/imunologia , Triticum/genética , Triticum/microbiologia , Sequência de Bases , Mapeamento Cromossômico , Segregação de Cromossomos/genética , Cruzamentos Genéticos , Eletroforese em Gel de Poliacrilamida , Ligação Genética , Marcadores Genéticos , Genótipo , Padrões de Herança/genética , Dados de Sequência Molecular , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Polimorfismo Genético , Plântula/genética , Plântula/microbiologia , Triticum/imunologia
19.
Comput Methods Biomech Biomed Engin ; 23(16): 1277-1286, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32692257

RESUMO

It is obvious that the mechanical properties of arterial tissue include compressibility, anisotropy, and the fact that the out-of-plane shear modulus is smaller than the shear modulus in the plane of the fibers. However, the last point is rarely considered when it comes to compressible anisotropic hyperelastic models. In order to acquire different shear moduli, we propose a modified hyperelastic model including the influence of strain invariants I5 and I7. The convergence and correctness of this model are verified through the hydrostatic tension test, uniaxial tension test, and shear deformation test. It turns out that our model correctly predicts an anisotropic response and volume change to hydrostatic tensile test and the fact that the out-of-plane shear modulus is always smaller than the shear modulus in the plane of the fibers in shear deformation test. We conclude that the influence of strain invariants I5 and I7 is great, especially in the shear deformation, so that it is necessary to include I5 and I7 in the compressible anisotropic hyperelastic model.


Assuntos
Elasticidade , Modelos Biológicos , Estresse Mecânico , Anisotropia , Artérias/patologia , Simulação por Computador , Análise de Elementos Finitos , Resistência ao Cisalhamento
20.
Phytopathology ; 99(10): 1209-15, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19740035

RESUMO

Stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici, is one of the most devastating foliar diseases of wheat (Triticum aestivum) worldwide. Growing resistant cultivars is the best approach for control of the disease. Although the stripe rust resistance in spring wheat cv. Zak has been circumvented by a group of races of the pathogen predominant in the United States since 2000, the resistance genes in Zak were unknown. To identify and map the genes for resistance to stripe rust, Zak was crossed with susceptible wheat genotype 'Avocet Susceptible'. Seedlings of the parents and F1, F2, and F3 progeny were tested with P. striiformis f. sp. tritici races PST-43 and PST-45 under controlled greenhouse conditions. Genetic analysis determined that Zak has a single dominant gene, designated as YrZak, conferring race-specific all-stage resistance. Resistance gene analog polymorphism (RGAP), simple sequence repeat (SSR), and sequence-tagged site (STS) techniques were used to identify molecular markers linked to YrZak. A linkage group of three RGAP, three SSR, and three STS markers was constructed for YrZak using 205 F3 lines. Amplification of the complete set of Chinese Spring nulli-tetrasomic lines with RGAP marker Xwgp102 indicated that YrZak is present on chromosome 2B. The three SSR markers further mapped YrZak to the long arm of chromosome 2B. Amplification of chromosome 2B deletion lines with SSR marker Xgwm501 further confirmed that YrZak is on chromosome 2BL. To determine the genetic distance between YrZak and Yr5, which also is present on chromosome 2BL, 300 F2 plants from cross Zak/Yr5 were tested with PST-43. Six susceptible plants were identified from the F2 population, indicating that YrZak and Yr5 are approximately 42 centimorgans apart. The results of race reactions and chromosomal locations indicated that YrZak is different from previously identified genes for resistance to stripe rust. This gene should be useful in monitoring virulence changes in the pathogen population and in studying host-pathogen interactions.


Assuntos
Basidiomycota/fisiologia , Mapeamento Cromossômico , Imunidade Inata/genética , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Triticum/genética , Triticum/microbiologia , Segregação de Cromossomos , Cromossomos de Plantas/genética , Genes de Plantas , Ligação Genética , Marcadores Genéticos , Genótipo , Padrões de Herança/genética , Polimorfismo Genético , Estações do Ano
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