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1.
Surg Endosc ; 34(1): 268-274, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31346748

RESUMO

BACKGROUND: Transoral endoscopic thyroidectomy vestibular approach (TOETVA) and total endoscopic thyroidectomy via areola approach (ETA) are commonly used endoscopic thyroidectomy approaches. This study compares the effectiveness of these approaches with conventional open thyroidectomy (COT) in terms of safety, associated trauma, and feasibility of central neck dissection in the treatment of papillary thyroid carcinoma (PTC). METHODS: This retrospective study included patients who underwent TOETVA (n = 100), ETA (n = 119), and COT (n = 289). All patients had a pathological diagnosis of PTC and underwent unilateral lobectomy and central neck dissection. We analyzed operative time, postoperative drainage volume, postoperative C-reactive protein (CRP), preoperative and postoperative white blood cell (WBC) count and parathyroid hormone (PTH) levels, parathyroid damage, hoarseness, total number of central lymph nodes, and number of metastatic central lymph nodes. RESULTS: The clinical characteristics across the three groups were similar except for patient sex and age. There was a higher proportion of young women in the TOETVA and ETA groups than in the COT group. There were significant differences between the three groups regarding operative time (P = 0.000), postoperative drainage volume (P = 0.000), postoperative CRP (P = 0.000), ∆WBC (P = 0.000), and length of postoperative hospital stay (P = 0.021); in the TOETVA and ETA groups, operative time (P = 0.445), postoperative drainage volume (P = 0.677), and length of postoperative hospital stay (P = 0.145) were not significantly different. The percentage of cases with parathyroid gland damage (P = 0.459) and hoarseness (P > 0.05) was similar in all groups. All three procedures were efficient in performing a central lymph node dissection. CONCLUSIONS: Although considered more traumatic, TOETVA and ETA are both safe treatment options for PTC. They can both achieve similar therapeutic effects of central neck dissection in the treatment of PTC when compared with open surgery.

2.
Am J Surg ; 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31818425

RESUMO

BACKGROUND: Optimal management for papillary thyroid microcarcinoma (PTMC) remains controversial. The purpose of this study was to explore risk factors predictive of cervical lymph node metastasis in conventional PTMCs. METHODS: Conventional PTMC patients (n = 2,404) undergoing surgery between 2010 and 2017 were grouped and analyzed according to the positivity of cervical lymph node. RESULTS: Central lymph node (CLN) metastases and lateral lymph node (LLN) metastases were observed in 915 (38.1%) and 184 (7.7%) cases, respectively. Multivariate analysis found that male (odds ratio [OR] = 1.974, p < 0.001), younger age (OR = 1.601, p < 0.001), tumor size (OR = 1.935, p < 0.001), extrathyroidal extension (ETE) (OR = 1.647, p < 0.001), multifocality (OR = 1.416, p < 0.001), and intrathyroidal spreading (OR = 3.355, p < 0.001) predicted increased CLN metastasis. In particular, younger age, multifocality, and intrathyroidal spreading were significantly associated with a high number of CLN metastases (n ≥ 5). The presence of CLN metastasis was strongly associated with LLN metastasis (OR = 5.426, p < 0.001). CONCLUSION: Male, younger age, tumor size, ETE, multifocality, and intrathyroidal spreading predict increased CLN metastasis in PTMCs. In patients with suspicious lateral lymphadenopathy, the presence of CLN metastasis is independently associated with LLN metastasis.

3.
Sci Rep ; 9(1): 17622, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772241

RESUMO

Among various tunable optical devices, tunable metamaterials have exhibited their excellent ability to dynamically manipulate lights in an efficient manner. However, for unchangeable optical properties of metals, electromagnetic resonances of popular metallic metamaterials are usually tuned indirectly by varying the properties or structures of substrates around the resonant unit cells, and the tuning of metallic metamaterials has significantly low efficiency. In this paper, a direct-tuning method for semiconductor metamaterials is proposed. The resonance strength and resonance frequencies of the metamaterials can be significantly tuned by controlling free carriers' distributions in unit cells under an applied voltage. This direct-tuning method has been verified in both two-dimensional and three-dimensional semiconductor metamaterials. In principle, the method allows for simplifying the structure of tunable metamaterials and opens the path to applications in ultrathin, linearly-tunable, and on-chip integrated optical components (e.g., tunable ultrathin lenses, nanoscale spatial light modulators and optical cavities with resonance modes switchable).

4.
Plant Dis ; 103(11): 2742-2750, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31509495

RESUMO

Stripe rust, also known as yellow rust, is a significant threat to wheat yield worldwide. Adult plant resistance (APR) is the preferred way to obtain durable protection. Chinese winter wheat cultivar Xinong1376 has maintained acceptable APR to stripe rust in field environments. To characterize APR in this cultivar, 190 F10 recombinant inbred lines (RILs) developed from Xiaoyan81 × Xinong1376 were evaluated for infection type and disease severity in fields either artificially or naturally inoculated. The population along with parents were genotyped using the Illumina 90K single-nucleotide polymorphism arrays. Six quantitative trait loci (QTL) were detected using the inclusive composite interval mapping method. QYr.nwafu-4AL and QYr.nwafu-6BL.3 conferred stable resistance in all environments, and likely corresponded to a gene-rich region on the long arm of chromosomes 4A and 6B. QYr.nwafu-5AL, QYr.nwafu-5BL, QYr.nwafu-3BL.1, and QYr.nwafu-3BL.2 were detected only in some environments but enhanced the level of resistance conferred by QYr.nwafu-4AL and QYr.nwafu-6BL.3. Kompetitive allele-specific PCR (KASP) markers developed for QYr.nwafu-4AL and QYr.nwafu-6BL.3 were confirmed in a subset of RILs and 133 wheat genotypes. The QTL on 4AL and 6BL with their linked KASP markers would be useful for marker-assisted selection to improve stripe rust resistance in breeding programs.


Assuntos
Resistência à Doença , Ligação Genética , Triticum , Resistência à Doença/genética , Genótipo , Fenótipo , Doenças das Plantas/genética , Triticum/classificação , Triticum/genética , Triticum/microbiologia
5.
Plant Dis ; 103(9): 2451-2459, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322491

RESUMO

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most devastating wheat diseases in Ethiopia. To study virulence genetics of the pathogen, 117 progeny isolates were produced through sexual reproduction of an Ethiopian isolate of the stripe rust pathogen on Berberis holstii plants under controlled conditions. The parental and progeny isolates were characterized by phenotyping on wheat lines carrying single Yr genes for resistance and genotyped using 10 polymorphic simple sequence repeated (SSR) markers. The progeny isolates were classified into 37 virulence phenotypes and 75 multilocus genotypes. The parental isolate and progeny isolates were all avirulent to resistance genes Yr5, Yr10, Yr15, Yr24, Yr32, YrTr1, YrSP, and Yr76 but virulent to Yr1 and Yr2, indicating that the parental isolate was homozygous avirulent or homozygous virulent at these loci. The progeny isolates segregated for virulence to 12 Yr genes. Virulence phenotypes to Yr6, Yr28, Yr43, and Yr44 were controlled by a single dominant gene; those to Yr7, Yr9, Yr17, Yr27, Yr25, Yr31, and YrExp2 were each controlled by two dominant genes; and the virulence phenotype to Yr8 was controlled by two complementary dominant genes. A linkage map was constructed with seven SSR markers, and 16 virulence loci corresponding to 11 Yr resistance genes were mapped with some loci linked to each other. These results are useful in understanding host-pathogen interactions and selecting resistance genes to develop wheat cultivars with highly effective resistance to stripe rust.


Assuntos
Basidiomycota , Berberis , Ligação Genética , Recombinação Genética , Virulência , Basidiomycota/genética , Basidiomycota/patogenicidade , Berberis/genética , Etiópia , Doenças das Plantas , Triticum/microbiologia , Virulência/genética
6.
Theor Appl Genet ; 132(5): 1409-1424, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30707240

RESUMO

KEY MESSAGE: Co-localization of a major QTL for wheat stripe rust resistance to a 3.9-cM interval on chromosome 6BL across both populations and another QTL on chromosome 2B with epistatic interaction. Cultivars with diverse resistance are the optimal strategy to minimize yield losses caused by wheat stripe rust (Puccinia striiformis f. sp. tritici). Two wheat populations involving resistant wheat lines P10078 and Snb"S" from CIMMYT were evaluated for stripe rust response in multiple environments. Pool analysis by Wheat660K SNP array showed that the overlapping interval on chromosome 6B likely harbored a major QTL between two populations. Then, linkage maps were constructed using KASP markers, and a co-localized locus with large effect on chromosome 6BL was detected using QTL analysis in both populations. The coincident QTL, named QYr.nwafu-6BL.2, explained 59.7% of the phenotypic maximum variation in the Mingxian 169 × P10078 and 52.5% in the Zhengmai 9023 × Snb"S" populations, respectively. This co-localization interval spanning 3.9 cM corresponds to ~ 30.5-Mb genomic region of the newest common wheat reference genome (IWGSC RefSeq v.1.0). In addition, another QTL was also detected on chromosome 2B in Zhengmai 9023 × Snb"S" population and it can accelerate expression of QYr.nwafu-6BL.2 to enhance resistance with epistatic interaction. Allowing for Pst response, marker genotypes, pedigree analysis and relative genetic distance, QYr.nwafu-6BL.2 is likely to be a distinct adult plant resistance QTL. Haplotype analysis of QYr.nwafu-6BL.2 revealed specific SNPs or alleles in the target region from a diversity panel of 176 unrelated wheat accessions. This QTL region provides opportunity for further map-based cloning, and haplotypes analysis enables pyramiding favorable alleles into commercial cultivars by marker-assisted selection.


Assuntos
Cromossomos de Plantas , Resistência à Doença/genética , Locos de Características Quantitativas , Triticum/genética , Mapeamento Cromossômico , Simulação por Computador , Epistasia Genética , Ligação Genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Triticum/microbiologia
7.
Plant Dis ; 103(3): 439-447, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30648483

RESUMO

Stripe rust caused by Puccinia striiformis f. sp. tritici threatens worldwide wheat production. Growing resistant cultivars is the best way to control this disease. Chinese wheat cultivar Qinnong 142 (QN142) has a high level of adult-plant resistance to stripe rust. To identify quantitative trait loci (QTLs) related to stripe rust resistance, we developed a recombinant inbred line (RIL) population from a cross between QN142 and susceptible cultivar Avocet S. The parents and 165 F6 RILs were evaluated in terms of their stripe rust infection type and disease severity in replicated field tests with six site-year environments. The parents and RILs were genotyped with single-nucleotide polymorphism (SNP) markers. Four stable QTLs were identified in QN142 and mapped to chromosome arms 1BL, 2AL, 2BL, and 6BS. The 1BL QTL was probably the known resistance gene Yr29, the 2BL QTL was in a resistance gene-rich region, and the 2AL and 6BS QTLs might be new. Kompetitive allele specific polymerase chain reaction markers developed from the SNP markers flanking these QTLs were highly polymorphic in a panel of 150 wheat cultivars and breeding lines. These markers could be used in marker-assisted selection for incorporating the stripe rust resistance QTL into new wheat cultivars.


Assuntos
Resistência à Doença , Genoma de Planta , Triticum , Basidiomycota/fisiologia , Cromossomos de Plantas , Resistência à Doença/genética , Marcadores Genéticos/genética , Genoma de Planta/genética , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Triticum/genética , Triticum/microbiologia
8.
Phytopathology ; 109(5): 819-827, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30644331

RESUMO

Breeding for resistance to stripe rust (caused by Puccinia striiformis f. tritici) is essential for reducing losses in yield and quality in wheat. To identify genes for use in breeding, a biparental population of 186 recombinant inbred lines (RILs) from a cross of the Chinese landrace Mingxian 169 and CIMMYT-derived line P9936 was evaluated in field nurseries either artificially or naturally inoculated in two crop seasons. Each of the RILs and parents was genotyped with the wheat 55K single-nucleotide polymorphism (SNP) 'Breeders' array and a genetic linkage map with 8,225 polymorphic SNP markers spanning 3,593.37 centimorgans was constructed. Two major quantitative trait loci (QTL) and two minor QTL were identified. The major QTL QYr.nwafu-3BS.2 and QYr.nwafu-7BL on chromosomes arms 3BS and 7BL were detected in all field locations and explained an average 20.4 and 38.9% of phenotypic variation stripe rust severity, respectively. QYr.nwafu-3BS.2 likely corresponds to the locus Yr30/Sr2 and QYr.nwafu-7BL may be a resistance allele identified previously in CIMMYT germplasm. The other minor QTL had limited individual effects but increased resistance when in combinations with other QTL. Markers linked to QYr.nwafu-7BL were converted to kompetitive allele-specific polymerase chain reaction markers and validated in a panel of wheat accessions. Wheat accessions carrying the same haplotype as P9936 at the identified SNP loci had lower average stripe rust severity than the average severity of all other haplotypes.


Assuntos
Basidiomycota/patogenicidade , Resistência à Doença/genética , Doenças das Plantas/genética , Triticum/genética , Mapeamento Cromossômico , Genes de Plantas , Fenótipo , Melhoramento Vegetal , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Triticum/microbiologia
9.
Artif Organs ; 43(6): 551-560, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30536407

RESUMO

Brain injury associated with deep hypothermic circulatory arrest (DHCA) has been recognized in patients with congenital heart diseases and those undergoing aortic arch surgeries. However, the preclinical investigation of long-term cerebral injury and recovery mechanisms related to DHCA has been restricted to a satisfactory recovery animal model with a determined recovery time. This study aimed to evaluate the feasibility of a long-term surviving DHCA model without blood priming in rats, in order to investigate the pathophysiology of long-term complications in further studies. Twelve Sprague-Dawley rats were divided into 2 groups: sham group (n = 3) and DHCA group (n = 9). The DHCA group was further assigned to the surviving time of postoperative day 2, 14, and 30 (n = 3, respectively). The entire cardiopulmonary bypass (CPB) circuit consisted of a modified reservoir, a custom-designed small-volume membrane oxygenator, a roller pump and a heater/cooler. A 24-G catheter was cannulated in the branch of the left femoral artery for arterial blood pressure monitoring. Cardiopulmonary bypass was established via the right external jugular vein-right atrium and tail artery. Rats were cooled to a rectal temperature of 18°C, followed by 30 minutes of DHCA with global ischemia. After re-warming for approximately 40 minutes, the animals were weaned from the CPB at 35.5°C. Blood gas and hemodynamic parameters were recorded preoperatively and intraoperatively, and at 2, 14, and 30 days postoperatively. Thereafter, the brains were perfusion fixed and histologically analyzed. All DHCA processes were successfully achieved, and none of the rats died. Blood gas analysis and hemodynamic parameters at each time point were normal, and vital signs of all rats were stable. Histopathologic deficits in the hippocampus (pathological score, surviving hippocampal neurons, and Ki67-positive neurons) manifested after 30 minutes of DHCA, which persisted for at least 14 days and recovered after 30 days. A novel and simple long-term recovery model of DHCA in rats was established in the present study, and histopathologic deficits were observed after clinically relevant 30-minute DHCA durations, in order to determine the 30-day recovery time frame.


Assuntos
Encéfalo/patologia , Parada Circulatória Induzida por Hipotermia Profunda/efeitos adversos , Animais , Encéfalo/irrigação sanguínea , Ponte Cardiopulmonar/instrumentação , Parada Circulatória Induzida por Hipotermia Profunda/instrumentação , Parada Circulatória Induzida por Hipotermia Profunda/métodos , Desenho de Equipamento , Hemodinâmica , Masculino , Ratos Sprague-Dawley
10.
Theor Appl Genet ; 132(2): 443-455, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30446795

RESUMO

KEY MESSAGE: A major stripe rust resistance QTL was mapped to a 0.4 centimorgan (cM) genetic region on the long arm of chromosome 7B, using combined genome-wide linkage mapping and bulk segregant analysis. The German winter wheat cv. Centrum has displayed high levels of adult plant stripe rust resistance (APR) in field environments for many years. Here, we used the combined genome-wide linkage mapping and pool-extreme genotyping to characterize the APR resistance. One hundred and fifty-one F2:7 recombinant inbred lines derived from a cross between susceptible landrace Mingxian 169 and Centrum were evaluated for stripe rust resistance in multiple environments and genotyped by the wheat 35K single nucleotide polymorphism (SNP) array. Three stable quantitative trait loci (QTL) were identified using QTL analysis across five field environments. To saturate the major QTL, the wheat 660K SNP array was also used to genotype bulked extremes. A major QTL named QYrcen.nwafu-7BL from Centrum was mapped in a 0.4 cM genetic interval flanking by AX-94556751 and AX-110366788 across a 2 Mb physical genomic region, explaining 19.39-42.81% of the total phenotypic variation. It is likely a previously uncharacterized QTL based on pedigree analysis, reaction response, genotyping data and map comparison. The SNP markers closely linked with QYrcen.nwafu-7BL were converted to KASP markers and validated in a subset of 120 wheat lines. A 211 F2 breeding population from a cross of an elite cultivar Xinong 979 with Centrum were developed for marker-based selection. Three selected lines with desirable agronomic traits and the positive alleles of both KASP markers showed acceptable resistance which should be used as resistance donors in wheat breeding programs. The other QTL QYrcen.nwafu-1AL and QYrcen.nwafu-4AL with additive effects could enhance the level of resistance conferred by QYrcen.nwafu-7BL.


Assuntos
Resistência à Doença/genética , Doenças das Plantas/genética , Locos de Características Quantitativas , Triticum/genética , Basidiomycota/patogenicidade , Mapeamento Cromossômico , Genes de Plantas , Ligação Genética , Genótipo , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Triticum/microbiologia
11.
Int J Surg ; 60: 22-27, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30389533

RESUMO

BACKGROUND: After totally endoscopic thyroidectomy (TET), patients usually suffer from voice, sensory, swallowing symptoms and they are also concerned with the postoperative cosmetic result. We compared the effects of subfascial dissection method with the subplatysmal method in TET on postoperative symptoms and cervical appearance. METHODS: 143 female patients who underwent totally endoscopic thyroid surgery were assigned to the subplatysmal approach group and subfascial approach group. The patient's voice symptoms were assessed using the Voice Handicap Index (VHI) questionnaire. Sensory function was assessed with subjective pain and light touch sensation. Swallowing symptoms were assessed using the Swallow Impairment Score (SIS) questionnaire and the 3 oz water swallow test. Neck cosmetic effect was assessed by postoperative recovery time of the suprasternal fossa and subjective satisfaction questionnaire. Each variable was measured preoperatively, at 2 weeks, 3 months and 6 months after operation. RESULTS: In both groups, the subjective voice, sensory and swallowing symptoms deteriorated at 2 weeks and improved at 3 months postoperatively. Indicators of VHI, SIS and 3 oz water swallow test returned to the preoperative level at 6 months after operation. In the subfascial group, SIS was significantly better than that of the subplatysmal group (p = 0.005) at 2 weeks after operation. The recovery time of the suprasternal fossa in the subfascial group was delayed (p = 0.158), compared with the subplatysmal group. CONCLUSION: The subfascial approach may have certain advantages in swallowing symptoms basing on the swallowing impairment test. However, the subplatysmal approach and the subfascial approach may have the same cosmetic effect.


Assuntos
Endoscopia/métodos , Esvaziamento Cervical/métodos , Tireoidectomia/métodos , Adulto , Estudos de Coortes , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/etiologia , Endoscopia/efeitos adversos , Fáscia , Feminino , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Estudos Prospectivos , Sensação/fisiologia , Sistema Musculoaponeurótico Superficial/cirurgia , Inquéritos e Questionários , Glândula Tireoide/cirurgia , Tireoidectomia/efeitos adversos , Resultado do Tratamento , Distúrbios da Voz/epidemiologia , Distúrbios da Voz/etiologia
12.
Opt Express ; 26(23): 30409-30419, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30469915

RESUMO

Fiber-optic laser-induced breakdown spectroscopy (FO-LIBS) has been employed in many applications because of the flexibility of optical fiber cable. However, the inhomogeneous elemental distribution of plasmas can cause a self-absorption effect and, hence, significantly hinder the determination of FO-LIBS. Here, to solve this flaw, we took iron (Fe), magnesium (Mg), and zinc (Zn) elements in aluminum alloy as examples to investigate the self-absorption reduction and accuracy improvement using spatially resolved FO-LIBS. Spatially resolved FO-LIBS means the spectra were collected at different positions along the direction parallel to the surface of the sample rather than at the center of the plasma. With this method, the self-absorption effect could be improved by selecting different acquisition positions along the X-axis. The root mean square error of cross-validations (RMSECV) for Fe, Mg, and Zn were reduced from 0.388, 0.348, and 0.097 wt. % to 0.172, 0.224, and 0.024 wt. %, respectively. Generally, spatial resolution is an effective method of self-absorption reduction and accuracy improvement in FO-LIBS.

13.
Appl Opt ; 57(22): 6451-6455, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30117877

RESUMO

The determination of potassium (K) content in ceramic raw materials provides important references for ceramic sintering. To realize rapid, in situ, and real-time analysis detection, a laser-induced breakdown spectroscopy (LIBS) system was set up to analyze K content in ceramic raw materials. However, the self-absorption was the serious influence on the accuracy of K element analysis. In this work, a method of profile fitting with Lorentz function was proposed to reduce the self-absorption effect in LIBS. After Lorentz fitting, the determination coefficient (R2 factor) for K element improved from 0.993 to 0.998, the root mean square error of cross-validation reduced from 0.458 wt. % to 0.145 wt. %, and the average relative error reduced from 13.769% to 5.121%. The results indicate that the Lorentz fitting can effectively reduce the self-absorption effect, and improve the accuracy of quantitative analysis for K element. According to the results, the proposed approach can be a promising method for determination of elements that suffer from self-absorption in LIBS.

14.
Front Plant Sci ; 9: 968, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30026752

RESUMO

Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is a devastating foliar disease that affects common wheat and barley throughout the world. The reasonable deployment of adult plant resistance (APR) wheat varieties is one of the best methods for controlling this disease. Wheat landraces are valuable resources for identifying the genes/QTLs responsible for disease resistance. Humai 15 is a Chinese spring wheat landrace and it has exhibited adequate levels of APR to the prevalent Pst races in field environments for many years. In this study, a population of 177 recombinant inbred lines (RILs) was derived from Humai 15 × Mingxian 169. After screening based on a 90K chip array using 45 RILs and Kompetitive Allelic Specific PCR marker genotyping for the population of RILs, a major effect QTL in Humai 15 was located on the centromere of chromosome 2B, where it accounted for up to 47.2% of the phenotypic variation. Two other minor QTL genes from Humai 15 were located on chromosome arms 3BS and 4BL. The Yr18 gene was identified on chromosome arm 7DS in Mingxian 169.

15.
Theor Appl Genet ; 131(8): 1777-1792, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29909527

RESUMO

KEY MESSAGE: A major stripe rust resistance QTL on chromosome 4BL was localized to a 4.5-Mb interval using comparative QTL mapping methods and validated in 276 wheat genotypes by haplotype analysis. CYMMIT-derived wheat line P10103 was previously identified to have adult plant resistance (APR) to stripe rust in the greenhouse and field. The conventional approach for QTL mapping in common wheat is laborious. Here, we performed QTL detection of APR using a combination of genome-wide scanning and extreme pool-genotyping. SNP-based genetic maps were constructed using the Wheat55 K SNP array to genotype a recombinant inbred line (RIL) population derived from the cross Mingxian 169 × P10103. Five stable QTL were detected across multiple environments. A fter comparing SNP profiles from contrasting, extreme DNA pools of RILs six putative QTL were located to approximate chromosome positions. A major QTL on chromosome 4B was identified in F2:4 contrasting pools from cross Zhengmai 9023 × P10103. A consensus QTL (LOD = 26-40, PVE = 42-55%), named QYr.nwafu-4BL, was defined and localized to a 4.5-Mb interval flanked by SNP markers AX-110963704 and AX-110519862 in chromosome arm 4BL. Based on stripe rust response, marker genotypes, pedigree analysis and mapping data, QYr.nwafu-4BL is likely to be a new APR QTL. The applicability of the SNP-based markers flanking QYr.nwafu-4BL was validated on a diversity panel of 276 wheat lines. The additional minor QTL on chromosomes 4A, 5A, 5B and 6A enhanced the level of resistance conferred by QYr.nwafu-4BL. Marker-assisted pyramiding of QYr.nwafu-4BL and other favorable minor QTL in new wheat cultivars should improve the level of APR to stripe rust.


Assuntos
Resistência à Doença/genética , Doenças das Plantas/genética , Locos de Características Quantitativas , Triticum/genética , Basidiomycota/patogenicidade , Mapeamento Cromossômico , Ligação Genética , Marcadores Genéticos , Genótipo , Fenótipo , Melhoramento Vegetal , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Triticum/microbiologia
16.
Theor Appl Genet ; 131(7): 1481-1496, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29666883

RESUMO

KEY MESSAGE: NGS-assisted super pooling emerging as powerful tool to accelerate gene mapping and haplotype association analysis within target region uncovering specific linkage SNPs or alleles for marker-assisted gene pyramiding. Conventional gene mapping methods to identify genes associated with important agronomic traits require significant amounts of financial support and time. Here, a single nucleotide polymorphism (SNP)-based mapping approach, RNA-Seq and SNP array assisted super pooling analysis, was used for rapid mining of a candidate genomic region for stripe rust resistance gene Yr26 that has been widely used in wheat breeding programs in China. Large DNA and RNA super-pools were genotyped by Wheat SNP Array and sequenced by Illumina HiSeq, respectively. Hundreds of thousands of SNPs were identified and then filtered by multiple filtering criteria. Among selected SNPs, over 900 were found within an overlapping interval of less than 30 Mb as the Yr26 candidate genomic region in the centromeric region of chromosome arm 1BL. The 235 chromosome-specific SNPs were converted into KASP assays to validate the Yr26 interval in different genetic populations. Using a high-resolution mapping population (> 30,000 gametes), we confined Yr26 to a 0.003-cM interval. The Yr26 target region was anchored to the common wheat IWGSC RefSeq v1.0 and wild emmer WEWSeq v.1.0 sequences, from which 488 and 454 kb fragments were obtained. Several candidate genes were identified in the target genomic region, but there was no typical resistance gene in either genome region. Haplotype analysis identified specific SNPs linked to Yr26 and developed robust and breeder-friendly KASP markers. This integration strategy can be applied to accelerate generating many markers closely linked to target genes/QTL for a trait of interest in wheat and other polyploid species.


Assuntos
Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/genética , Polimorfismo de Nucleotídeo Único , Triticum/genética , Basidiomycota , Ligação Genética , Genótipo , Haplótipos , Mapeamento Físico do Cromossomo , Doenças das Plantas/microbiologia , Triticum/microbiologia
17.
Front Plant Sci ; 9: 18, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29403523

RESUMO

Cyclic nucleotide gated channels (CNGCs) play multifaceted roles in plants, particularly with respect to signaling processes associated with abiotic stress signaling and during host-pathogen interactions. Despite key roles during plant survival and response to environment, little is known about the activity and function of CNGC family in common wheat (Triticum aestivum L.), a key stable food around the globe. In this study, we performed a genome-wide identification of CNGC family in wheat and identified a total 47 TaCNGCs in wheat, classifying these genes into four major groups (I-IV) with two sub-groups (IVa and IVb). Sequence analysis revealed the presence of several conserved motifs, including a phosphate binding cassette (PBC) and a "hinge" region, both of which have been hypothesized to be critical for the function of wheat CNGCs. During wheat infection with Pst, the transcript levels of TaCNGC14 and TaCNGC16, both members of group IVb, showed significant induction during a compatible interaction, while a reduction in gene expression was observed in incompatible interactions. In addition, TaCNGC14 and TaCNGC16 mRNA accumulation was significantly influenced by exogenously applied hormones, including abscisic acid (ABA), methyl jasmonate (MeJA), and salicylic acid (SA), suggesting a role in hormone signaling and/or perception. Silencing of TaCNGC14 and TaCNGC16 limited Pst growth and increased wheat resistance against Pst. The results presented herein contribute to our understanding of the wheat CNGC gene family and the mechanism of TaCNGCs signaling during wheat-Pst interaction.

18.
Theor Appl Genet ; 131(1): 43-58, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28965125

RESUMO

KEY MESSAGE: High-throughput SNP array analysis of pooled extreme phenotypes in a segregating population by KASP marker genotyping permitted rapid, cost-effective location of a stripe rust resistance QTL in wheat. German wheat cultivar "Friedrichswerther" has exhibited high levels of adult plant resistance (APR) to stripe rust in field environments for many years. F2:3 lines and F6 recombinant inbred line (RILs) populations derived from a cross between Friedrichswerther and susceptible landrace Mingxian 169 were evaluated in the field in 2013, 2016 and 2017. Illumina 90K iSelect SNP arrays were used to genotype bulked extreme pools and parents; 286 of 1135 polymorphic SNPs were identified on chromosome 6B. Kompetitive Allele-Specific PCR (KASP) markers were used to verify the chromosome region associated with the resistance locus. A linkage map was constructed with 18 KASP-SNP markers, and a major effect QTL was identified within a 1.4 cM interval flanked by KASP markers IWB71602 and IWB55937 in the region 6BL3-0-0.36. The QTL, named QYr.nwafu-6BL, was stable across environments, and explained average 54.4 and 47.8% of the total phenotypic variation in F2:3 lines and F6 RILs, respectively. On the basis of marker genotypes, pedigree analysis and relative genetic distance QYr.nwafu-6BL is likely to be a new APR QTL. Combined high-throughput SNP array genotyping of pooled extremes and validation by KASP assays lowers sequencing costs compared to genome-wide association studies with SNP arrays, and more importantly, permits rapid isolation of major effect QTL in hexaploid wheat as well as improving accuracy of mapping in the QTL region. QYr.nwafu-6BL with flanking KASP markers developed and verified in a subset of 236 diverse lines can be used in marker-assisted selection to improve stripe rust resistance in breeding programs.


Assuntos
Resistência à Doença/genética , Genes de Plantas , Doenças das Plantas/genética , Triticum/genética , Basidiomycota , Mapeamento Cromossômico , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo de Nucleotídeo Único , Poliploidia , Locos de Características Quantitativas , Triticum/microbiologia
19.
Phytopathology ; 108(1): 103-113, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28832276

RESUMO

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most devastating diseases of wheat worldwide. Growing resistant cultivars is considered the best approach to manage this disease. In order to identify the resistance gene(s) in wheat line 03031-1-5 H62, which displayed high resistance to stripe rust at adult plant stage, a cross was made between 03031-1-5 H62 and susceptible cultivar Avocet S. The mapping population was tested with Chinese P. striiformis f. sp. tritici race CYR32 through artificial inoculation in a field in Yangling, Shaanxi Province and under natural infection in Tianshui, Gansu Province. The segregation ratios indicated that the resistance was conferred by a single dominant gene, temporarily designated as YrH62. A combination of bulked segregant analysis (BSA) with wheat 90K single nucleotide polymorphism (SNP) array was used to identify molecular markers linked to YrH62. A total of 376 polymorphic SNP loci identified from the BSA analysis were located on chromosome 1B, from which 35 kompetitive allele-specific PCR (KASP) markers selected together with 84 simple sequence repeat (SSR) markers on 1B were used to screen polymorphism and a chromosome region associated with rust resistance was identified. To saturate the chromosomal region covering the YrH62 locus, a 660K SNP array was used to identify more SNP markers. To develop tightly linked markers for marker-assisted selection of YrH62 in wheat breeding, 18 SNPs were converted into KASP markers. A final linkage map consisting of 15 KASP and 3 SSR markers was constructed with KASP markers AX-109352427 and AX-109862469 flanking the YrH62 locus in a 1.0 cM interval. YrH62 explained 63.8 and 69.3% of the phenotypic variation for disease severity and infection type, respectively. YrH62 was located near the centromeric region of chromosome 1BS based on the positions of the SSR markers in 1B deletion bins. Based on the origin, responses to P. striiformis f. sp. tritici races, and marker distances, YrH62 is likely different from the other reported stripe rust resistance genes/quantitative trait loci on 1B. The gene and tightly linked KASP markers will be useful for breeding wheat cultivars with resistance to stripe rust.


Assuntos
Basidiomycota/fisiologia , Cromossomos de Plantas/genética , Resistência à Doença/genética , Doenças das Plantas/imunologia , Polimorfismo de Nucleotídeo Único/genética , Triticum/genética , Alelos , Mapeamento Cromossômico , Genótipo , Técnicas de Genotipagem , Repetições de Microssatélites/genética , Fenótipo , Doenças das Plantas/microbiologia , Triticum/microbiologia
20.
J Pathol Transl Med ; 51(6): 528-532, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29046513

RESUMO

Cytology in China developed from nothing and underwent a long journey from gynecologic cytology to that of all organs, laying a solid foundation for new developments in the 21st century. Thyroid fine-needle aspiration (FNA) was primarily developed in an endocrinology department and then in the clinical laboratory department or pathology department in the 1970-80s. Wrights staining is popular in endocrine and clinical laboratory departments, while hematoxylin and eosin staining is common in pathology. Liquid based cytology is not common in thyroid FNA cytology, while BRAF V600E mutation analysis has been the most popular molecular test. The history and practice of thyroid FNA practice in China were reviewed based on retrospective study of the practice in Qilu Hospital of Shandong University.

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