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1.
Opt Lett ; 48(7): 1934-1937, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37221803

RESUMEN

The manufacturing and characterization of freeform optical surfaces are influenced by their high sensitivity to misalignments. In this work, the computational sampling moiré technique combined with phase extraction is developed for the precise alignment of freeform optics during fabrication and in metrology applications. This novel, to the best of our knowledge, technique achieves near-interferometry-level precision in a simple and compact configuration. This robust technology can be applied to industrial manufacturing platforms (such as diamond turning machines, lithography, and other micro-nano-machining techniques) as well as their metrology equipment. In a demonstration of computational data processing and precision alignment using this method, iterative manufacturing of freeform optical surfaces with a final-form accuracy of about 180 nm was accomplished.

2.
Mol Biol Rep ; 50(10): 8213-8224, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37561326

RESUMEN

BACKGROUND: ToxA, a necrotrophic effector protein, is present in the genome of fungal species like Parastagnospora nodorum, Pyrenophora tritici-repentis and Bipolaris sorokiniana. Tsn1 is the sensitivity gene in the host whose presence indicates more susceptibility to ToxA carrying pathogen, and ToxA-Tsn1 interaction follows an inverse gene-for-gene relationship. METHODS AND RESULTS: The present study involved cloning and expressing the ToxA1 haplotype from B. sorokiniana. It was found that the amplicon exhibited an expected product size of 471 bp. Sequence analysis of the ToxA1 nucleotide sequence revealed the highest identity, 99.79%, with P. tritici-repentis. The protein expression analysis showed peak expression at 16.5 kDa. Phylogenetic analysis of the ToxA1 sequence from all the Bipolaris isolates formed an independent clade along with P. tritici-repentis and diverged from P. nodorum. ToxA-Tsn1 interaction was studied in 18 wheat genotypes (11 Tsn1 and 7 tsn1) at both seedling and adult stages, validating the inverse gene-for-gene relationship, as the toxin activity was highest in the K68 genotype (Tsn1) and lowest in WAMI280 (tsn1). CONCLUSION: The study indicates that the haplotype ToxA1 is prevailing in the Indian population of B. sorokiniana. It would be desirable for wheat breeders to select genotypes with tsn1 locus for making wheat resistant to spot blotch.


Asunto(s)
Enfermedades de las Plantas , Triticum , Triticum/genética , Triticum/microbiología , Haplotipos/genética , Filogenia , India , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología
3.
BMC Plant Biol ; 22(1): 618, 2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36577935

RESUMEN

BACKGROUND: During the last few decades, the diverse sources of resistance, several genes and QTLs for spot blotch resistance have been identified. However, a large set of germplasm lines are still unexplored that have the potential to develop highly resistant wheat cultivars for the target environments. Therefore, the identification of new sources of resistance to spot blotch is essential for breeding programmes to develop spot blotch resistant cultivars and sustain wheat production. The association mapping panel of 294 diverse bread wheat accessions was used to explore new sources of spot blotch disease resistance and to identify genomic regions using genome wide association analysis (GWAS). The genotypes were tested in replicated trials for spot blotch disease at three major hot spots in India (Varanasi in UP, Pusa in Bihar, and Cooch Behar in West Bengal). The area under the disease progress curve (AUDPC) was calculated to assess the level of resistance in each genotype. RESULTS: A total of 19 highly and 76 moderately resistant lines were identified. Three accessions (EC664204, IC534306 and IC535188) were nearly immune to spot blotch disease. The genotyping of all accessions resulted in a total of 16,787 high-quality polymorphic SNPs. The GWAS was performed using a Compressed Mixed Linear Model (CMLM) and a Mixed Linear Model (MLM). A total of seven significant MTAs, common in both the models and consistent across the environment, were further validated to develop KASP markers. Four MTAs (AX-94710084, AX-94865722, AX-95135556, and AX-94529408) on three chromosomes (2AL, 2BL, and 3BL) have been successfully validated through the KASP marker. CONCLUSIONS: The new source of resistance was identified from unexplored germplasm lines. The genomic regions identified through GWAS were validated through KASP markers. The marker information and the highly resistant sources are valuable resources to rapidly develop immune or near immune wheat varieties.


Asunto(s)
Ascomicetos , Resistencia a la Enfermedad , Resistencia a la Enfermedad/genética , Triticum/genética , Estudio de Asociación del Genoma Completo , Alelos , Ascomicetos/genética , Fitomejoramiento , Polimorfismo de Nucleótido Simple/genética , Enfermedades de las Plantas/genética
4.
Theor Appl Genet ; 135(6): 1965-1983, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35416483

RESUMEN

KEY MESSAGE: Genomic selection is a promising tool to select for spot blotch resistance and index-based selection can simultaneously select for spot blotch resistance, heading and plant height. A major biotic stress challenging bread wheat production in regions characterized by humid and warm weather is spot blotch caused by the fungus Bipolaris sorokiniana. Since genomic selection (GS) is a promising selection tool, we evaluated its potential for spot blotch in seven breeding panels comprising 6736 advanced lines from the International Maize and Wheat Improvement Center. Our results indicated moderately high mean genomic prediction accuracies of 0.53 and 0.40 within and across breeding panels, respectively which were on average 177.6% and 60.4% higher than the mean accuracies from fixed effects models using selected spot blotch loci. Genomic prediction was also evaluated in full-sibs and half-sibs panels and sibs were predicted with the highest mean accuracy (0.63) from a composite training population with random full-sibs and half-sibs. The mean accuracies when full-sibs were predicted from other full-sibs within families and when full-sibs panels were predicted from other half-sibs panels were 0.47 and 0.44, respectively. Comparison of GS with phenotypic selection (PS) of the top 10% of resistant lines suggested that GS could be an ideal tool to discard susceptible lines, as greater than 90% of the susceptible lines discarded by PS were also discarded by GS. We have also reported the evaluation of selection indices to simultaneously select non-late and non-tall genotypes with low spot blotch phenotypic values and genomic-estimated breeding values. Overall, this study demonstrates the potential of integrating GS and index-based selection for improving spot blotch resistance in bread wheat.


Asunto(s)
Ascomicetos , Triticum , Pan , Genómica , Humanos , Fenotipo , Fitomejoramiento , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Triticum/genética , Triticum/microbiología
5.
Mol Breed ; 42(4): 21, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37309458

RESUMEN

Improvement of grain protein content (GPC), loaf volume, and resistance to rusts was achieved in 11 Indian wheat cultivars that are widely grown in four different agro-climatic zones of India. This involved use of marker-assisted backcross breeding (MABB) for introgression and pyramiding of the following genes: (i) the high GPC gene Gpc-B1; (ii) HMW glutenin subunits 5 + 10 at Glu-D1 loci, and (iii) rust resistance genes, Yr36, Yr15, Lr24, and Sr24. GPC increased by 0.8 to 3.3%, although high GPC was generally associated with yield penalty. Further selection among high GPC lines allowed identification of progenies with higher GPC associated with improvement in 1000-grain weight and grain yield in the backgrounds of the following four cultivars: NI5439, UP2338, UP2382, and HUW468. The high GPC progenies (derived from NI5439) were also improved for grain quality using HMW glutenin subunits 5 + 10 at Glu-D1 loci. Similarly, progenies combining high GPC and rust resistance were obtained in the backgrounds of following five cultivars: Lok1, HD2967, PBW550, PBW621, and DBW1. The improved pre-bred lines developed following multi-institutional effort should prove a valuable source for the development of cultivars with improved nutritional quality and rust resistance in the ongoing wheat breeding programmes. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01277-w.

6.
Appl Opt ; 61(17): 5179-5188, 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-36256200

RESUMEN

Superfine optical components are necessary for advanced engineering applications such as x-ray optics, high-power lasers, lithography, synchrotron optics, laser-based sensors, etc. Fabrication of such superfine surfaces is one of the major challenges for optical and semiconductor industries. This research focuses on the development of a magnetic nanoparticle-based nanoabrasive for superfine optical polishing. The superparamagnetic iron oxide nanoparticle (SPION)-based nanoabrasive is synthesized via a hydrothermal route by employing cost-effective precursors. Detailed characterizations of the prepared nanoabrasive are presented. Transmission electron microscopy results confirm the irregular cubic and spherical shaped morphology of the SPION nanoabrasive along with particle size distribution varying from 10-60 nm, enabling the homogenous cutting effect of the aqueous slurry for polishing. Furthermore, the high surface area and pore size are determined by Brunauer-Emmet-Teller analysis and found to be 30.98m2/g and 6.13 nm, respectively, providing homogenous distribution of the nanoabrasive on the surface of a BK7 substrate for material removal. Application of the developed SPION abrasive is demonstrated for superfinish optical polishing on a BK7 optical disc. The experimental polishing results show superfine surface finishing with an average roughness value of 3.5 Å. The superparamagnetic property of the developed nanoabrasive is confirmed by alternative gradient magnetometry, and it helps in recovering the used nanoabrasive after polishing. Moreover, the polishing performance of the SPION nanoabrasives is compared with a cerium nanoabrasive, which is also synthesized in this study.

7.
J Biosoc Sci ; 53(1): 121-136, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32122418

RESUMEN

Using longitudinal data from the first and second waves of the Young Lives Study (YLS) in Ethiopia, India (Andhra Pradesh), Peru and Vietnam, conducted in 2002 and 2006-07, and a repeated measures mixed model, this study examined the effect of the use of solid fuels for cooking on childhood stunting among children aged 5-76 months. The analysis showed that in all four populations, the average height-for-age z-score (HAZ score) was much lower among children living in households using solid fuels than among children in households using cleaner fuels for cooking. The average HAZ score was lower among children living in households that used solid fuels in both waves of the YLS compared with those whose households used solid fuels in only one of the two waves. A significant reduction was noted in the average HAZ score between the two waves in all countries except Ethiopia. The results of the repeated measures mixed model suggest that household use of solid fuels was significantly associated with lower HAZ scores in all populations, except Ethiopia. The findings also indicate that the reduction in the HAZ scores between waves 1 and 2 was not statistically significant by the type of cooking fuel after controlling for potential confounding factors. The study provides further evidence of a strong association between household use of solid fuels and childhood stunting in low- and middle-income countries using longitudinal data. The findings highlight the need to reduce exposure to smoke from the combustion of solid fuels, by shifting households to cleaner cooking fuels, where feasible, by providing cooking stoves with improved combustion of solid fuels and improved venting, and by designing and implementing public information campaigns to inform people about the health risks of exposure to cooking smoke.


Asunto(s)
Contaminación del Aire Interior/efectos adversos , Salud Infantil , Carbón Mineral/efectos adversos , Culinaria/métodos , Países en Desarrollo , Trastornos del Crecimiento/epidemiología , Madera/efectos adversos , Adolescente , Contaminación del Aire Interior/análisis , Niño , Preescolar , Análisis de Datos , Etiopía/epidemiología , Composición Familiar , Femenino , Trastornos del Crecimiento/etiología , Humanos , Renta , India/epidemiología , Lactante , Estudios Longitudinales , Masculino , Perú/epidemiología , Vietnam/epidemiología , Adulto Joven
8.
Plant Dis ; 104(1): 71-81, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31697221

RESUMEN

The ToxA-Tsn1 system is an example of an inverse gene-for-gene relationship. The gene ToxA encodes a host-selective toxin (HST) which functions as a necrotrophic effector and is often responsible for the virulence of the pathogen. The genomes of several fungal pathogens (e.g., Pyrenophora tritici-repentis, Parastagonospora nodorum, and Bipolaris sorokiniana) have been shown to carry the ToxA gene. Tsn1 is a sensitivity gene in the host, whose presence generally helps a ToxA-positive pathogen to cause spot blotch in wheat. Cultivars lacking Tsn1 are generally resistant to spot blotch; this resistance is attributed to a number of other known genes which impart resistance in the absence of Tsn1. In the present study, 110 isolates of B. sorokiniana strains, collected from the ME5A and ME4C megaenvironments of India, were screened for the presence of the ToxA gene; 77 (70%) were found to be ToxA positive. Similarly, 220 Indian wheat cultivars were screened for the presence of the Tsn1 gene; 81 (36.8%) were found to be Tsn1 positive. When 20 wheat cultivars (11 with Tsn1 and 9 with tsn1) were inoculated with ToxA-positive isolates, seedlings of only those carrying the Tsn1 allele (not tsn1) developed necrotic spots surrounded by a chlorotic halo. No such distinction between Tsn1 and tsn1 carriers was observed when adult plants were inoculated. This study suggests that the absence of Tsn1 facilitated resistance against spot blotch of wheat. Therefore, the selection of wheat genotypes for the absence of the Tsn1 allele can improve resistance to spot blotch.


Asunto(s)
Ascomicetos , Interacciones Huésped-Patógeno , Triticum , Virulencia , Ascomicetos/genética , Ascomicetos/patogenicidad , Resistencia a la Enfermedad/genética , Genes Fúngicos/genética , Genes de Plantas/genética , Interacciones Huésped-Patógeno/genética , India , Triticum/genética , Triticum/microbiología , Virulencia/genética
9.
Physiol Mol Biol Plants ; 24(5): 909-920, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30150865

RESUMEN

Grain traits are important agronomic attributes with the market value as well as milling yield of bread wheat. In the present study, quantitative trait loci (QTL) regulating grain traits in wheat were identified. Data for grain area size (GAS), grain width (GWid), factor form density (FFD), grain length-width ratio (GLWR), thousand grain weight (TGW), grain perimeter length (GPL) and grain length (GL) were recorded on a recombinant inbred line derived from the cross of NW1014 × HUW468 at Meerut and Varanasi locations. A linkage map of 55 simple sequence repeat markers for 8 wheat chromosomes was used for QTL analysis by Composite interval mapping. Eighteen QTLs distributed on 8 chromosomes were identified for seven grain traits. Of these, five QTLs for GLWR were found on chromosomes 1A, 6A, 2B, and 7B, three QTLs for GPL were located on chromosomes 4A, 5A and 7B and three QTLs for GAS were mapped on 5D and 7D. Two QTLs were identified on chromosomes 4A and 5A for GL and two QTLs for GWid were identified on chromosomes 7D and 6A. Similarly, two QTLs for FFD were found on chromosomes 1A and 5D. A solitary QTL for TGW was identified on chromosome 2B. For several traits, QTLs were also co-localized on chromosomes 2B, 4A, 5A, 6A, 5D, 7B and 7D. The QTLs detected in the present study may be validated for specific crosses and then used for marker-assisted selection to improve grain quality in bread wheat.

10.
Plant J ; 86(1): 35-49, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26932764

RESUMEN

Spot blotch disease, caused by Bipolaris sorokiniana, is an important threat to wheat, causing an annual loss of ~17%. Under epidemic conditions, these losses may be 100%, yet the molecular responses of wheat to spot blotch remain almost uncharacterized. Moreover, defense-related phytohormone signaling genes have been poorly characterized in wheat. Here, we have identified 18 central components of salicylic acid (SA), jasmonic acid (JA), ethylene (ET), and enhanced disease susceptibility 1 (EDS1) signaling pathways as well as the genes of the phenylpropanoid pathway in wheat. In time-course experiments, we characterized the reprogramming of expression of these pathways in two contrasting genotypes: Yangmai #6 (resistant to spot blotch) and Sonalika (susceptible to spot blotch). We further evaluated the performance of a population of recombinant inbred lines (RILs) by crossing Yangmai#6 and Sonalika (parents) and subsequent selfing to F10 under field conditions in trials at multiple locations. We characterized the reprogramming of defense-related signaling in these RILs as a consequence of spot blotch attack. During resistance to spot blotch attack, wheat strongly elicits SA signaling (SA biogenesis as well as the NPR1-dependent signaling pathway), along with WRKY33 transcription factor, followed by an enhanced expression of phenylpropanoid pathway genes. These may lead to accumulation of phenolics-based defense metabolites that may render resistance against spot blotch. JA signaling may synergistically contribute to the resistance. Failure to elicit SA (and possibly JA) signaling may lead to susceptibility against spot blotch infection in wheat.


Asunto(s)
Ascomicetos/fisiología , Enfermedades de las Plantas/inmunología , Reguladores del Crecimiento de las Plantas/metabolismo , Inmunidad de la Planta , Transducción de Señal , Triticum/fisiología , Ascomicetos/citología , Ciclopentanos/metabolismo , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Endogamia , Anotación de Secuencia Molecular , Oxilipinas/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/inmunología , Hojas de la Planta/fisiología , Ácido Salicílico/metabolismo , Triticum/genética , Triticum/inmunología
11.
Photosynth Res ; 132(1): 13-66, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27815801

RESUMEN

Using chlorophyll (Chl) a fluorescence many aspects of the photosynthetic apparatus can be studied, both in vitro and, noninvasively, in vivo. Complementary techniques can help to interpret changes in the Chl a fluorescence kinetics. Kalaji et al. (Photosynth Res 122:121-158, 2014a) addressed several questions about instruments, methods and applications based on Chl a fluorescence. Here, additional Chl a fluorescence-related topics are discussed again in a question and answer format. Examples are the effect of connectivity on photochemical quenching, the correction of F V /F M values for PSI fluorescence, the energy partitioning concept, the interpretation of the complementary area, probing the donor side of PSII, the assignment of bands of 77 K fluorescence emission spectra to fluorescence emitters, the relationship between prompt and delayed fluorescence, potential problems when sampling tree canopies, the use of fluorescence parameters in QTL studies, the use of Chl a fluorescence in biosensor applications and the application of neural network approaches for the analysis of fluorescence measurements. The answers draw on knowledge from different Chl a fluorescence analysis domains, yielding in several cases new insights.


Asunto(s)
Clorofila/química , Clorofila/metabolismo , Fluorescencia , Técnicas Biosensibles , Clorofila A , Productos Agrícolas , Complejo de Citocromo b6f/metabolismo , Citocromos b6/metabolismo , Transporte de Electrón , Herbicidas/toxicidad , Luz , Complejo de Proteína del Fotosistema I/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Estrés Fisiológico , Temperatura , Árboles
12.
Clin Transplant ; 31(1)2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27862341

RESUMEN

Islet transplantation is a minimally invasive ß-cell replacement strategy. Islet transplantation is a reimbursed treatment in Norway. Here, we summarize the cost and clinical outcome of 31 islet transplantations performed at Oslo University Hospital (OUS) from January 2010 to June 2015. Patients were retrospectively divided into three groups. Thirteen patients received either one or two islet transplantation alone (ITA), while five patients received islet transplantation after previous solid organ transplantation. For the group receiving 2 ITA, Kaplan-Meier estimates show an insulin independence of 20% more than 4 years after their last transplantation. An estimated 70% maintain at least partial graft function, defined as fasting C-peptide >0.1 nmol L-1 , and 47% maintain a HbA1c below 6.5% or 2 percent points lower than before ITA. For all groups combined, we estimate that 44% of the patients have a 50% reduction in insulin requirement 4 years after the initial islet transplantation. The average cost for an islet transplantation procedure was 347 297±60 588 NOK, or 35 424±6182 EUR, of which isolation expenses represent 34%. We hereby add to the common pool of growing experience with islet transplantation and also describe the cost of the treatment at our center.


Asunto(s)
Diabetes Mellitus Tipo 1/economía , Rechazo de Injerto/economía , Trasplante de Islotes Pancreáticos/economía , Complicaciones Posoperatorias/economía , Adulto , Diabetes Mellitus Tipo 1/cirugía , Femenino , Estudios de Seguimiento , Rechazo de Injerto/epidemiología , Supervivencia de Injerto , Humanos , Incidencia , Trasplante de Islotes Pancreáticos/métodos , Masculino , Persona de Mediana Edad , Noruega/epidemiología , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
13.
Scand Cardiovasc J ; 51(1): 1-7, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27248460

RESUMEN

OBJECTIVES: Growing number of patients with terminal heart failure and a shortage of heart donors have increased use of short- and long-term mechanical circulatory support (MCS). Few studies have analyzed survival rates and healthcare costs for heart transplantation (HTx), with or without extracorporeal membrane oxygenation (ECMO) and left ventricular assist device (LVAD). DESIGN: In a retrospective, single-center study, data were analyzed from patients listed for HTx who died on the waiting list (DWL, n = 12), underwent HTx (n = 206), had ECMO as bridge to HTx (ECHTx, n = 15), or received LVAD treatment, either isolated (LVAD, n = 19) or bridging to HTx (LVADHTx, n = 26) during 2005-2012. Survival and hospital costs were assessed. RESULTS: One- and five-year survival rates were 96% and 83% for the LVADHTx group, 92% and 81% for HTx, 70% and 70% for ECHTx, 48% and 36% for LVAD and 0% for the DWL group (overall survival, p < 0.001). Total hospital cost at one year was $102,101 ± 202,604 for DWL, $151,685 ± 86,892 for HTx, $292,078 ± 101,915 for ECHTx, $427,337 ± 365,154 for LVAD, and $600,897 ± 198,109 for LVADHTx. CONCLUSION: The LVADHTx and HTx groups showed excellent one- and five-year survival. The combined group of DWL and HTx patients had similar survival to the combined groups of MCS, but use of LVAD pre-transplant quadrupled the cost.


Asunto(s)
Oxigenación por Membrana Extracorpórea/economía , Insuficiencia Cardíaca/economía , Insuficiencia Cardíaca/terapia , Trasplante de Corazón/economía , Corazón Auxiliar/economía , Costos de Hospital , Evaluación de Procesos, Atención de Salud/economía , Adolescente , Adulto , Anciano , Terapia Combinada , Oxigenación por Membrana Extracorpórea/efectos adversos , Oxigenación por Membrana Extracorpórea/mortalidad , Femenino , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Trasplante de Corazón/efectos adversos , Trasplante de Corazón/mortalidad , Corazón Auxiliar/efectos adversos , Humanos , Estimación de Kaplan-Meier , Tiempo de Internación/economía , Masculino , Persona de Mediana Edad , Modelos Económicos , Noruega , Diseño de Prótesis , Recuperación de la Función , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Función Ventricular Izquierda , Adulto Joven
14.
J Bacteriol ; 198(13): 1868-1882, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27137496

RESUMEN

UNLABELLED: The absence of PtsN, the terminal phosphoacceptor of the phosphotransferase system comprising PtsP-PtsO-PtsN, in Escherichia coli confers a potassium-sensitive (K(s)) phenotype as the external K(+) concentration ([K(+)]e) is increased above 5 mM. A growth-inhibitory increase in intracellular K(+) content, resulting from hyperactivated Trk-mediated K(+) uptake, is thought to cause this K(s) We provide evidence that the K(s) of the ΔptsN mutant is associated with K(+) limitation. Accordingly, the moderate K(s) displayed by the ΔptsN mutant was exacerbated in the absence of the Trk and Kup K(+) uptake transporters and was associated with reduced cellular K(+) content. Conversely, overproduction of multiple K(+) uptake proteins suppressed the K(s) Expression of PtsN variants bearing the H73A, H73D, and H73E substitutions of the phosphorylation site histidine of PtsN complemented the K(s) Absence of the predicted inner membrane protein YcgO (also called CvrA) suppressed the K(s), which was correlated with elevated cellular K(+) content in the ΔptsN mutant, but the ΔptsN mutation did not alter YcgO levels. Heterologous overexpression of ycgO also led to K(s) that was associated with reduced cellular K(+) content, exacerbated by the absence of Trk and Kup and alleviated by overproduction of Kup. Our findings are compatible with a model that postulates that K(s) in the ΔptsN mutant occurs due to K(+) limitation resulting from activation of K(+) efflux mediated by YcgO, which may be additionally stimulated by [K(+)]e, implicating a role for PtsN (possibly its dephosphorylated form) as an inhibitor of YcgO activity. IMPORTANCE: This study examines the physiological link between the phosphotransferase system comprising PtsP-PtsO-PtsN and K(+) ion metabolism in E. coli Studies on the physiological defect that renders an E. coli mutant lacking PtsN to be growth inhibited by external K(+) indicate that growth impairment results from cellular K(+) limitation that is mediated by YcgO, a predicted inner membrane protein. Additional observations suggest that dephospho-PtsN may inhibit and external K(+) may stimulate K(+) limitation mediated by YcgO. It is speculated that YcgO-mediated K(+) limitation may be an output of a response to certain stresses, which by modulating the phosphotransfer capacity of the PtsP-PtsO-PtsN phosphorelay leads to growth cessation and stress tolerance.


Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/metabolismo , Potasio/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/genética
15.
J Biol Chem ; 290(12): 7685-92, 2015 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-25605722

RESUMEN

The ACTH receptor, known as the melanocortin-2 receptor (MC2R), plays an important role in regulating and maintaining adrenocortical function. MC2R is a subtype of the melanocortin receptor (MCR) family and has unique characteristics among MCRs. Endogenous ACTH is the only endogenous agonist for MC2R, whereas the melanocortin peptides α-, ß-, and γ-melanocyte-stimulating hormone and ACTH are full agonists for all other MCRs. In this study, we examined the molecular basis of MC2R responsible for ligand selectivity using ACTH analogs and MC2R mutagenesis. Our results indicate that substitution of Phe(7) with D-Phe or D-naphthylalanine (D-Nal(2')) in ACTH(1-24) caused a significant decrease in ligand binding affinity and potency. Substitution of Phe(7) with D-Nal(2') in ACTH(1-24) did not switch the ligand from agonist to antagonist at MC2R, which was observed in MC3R and MC4R. Substitution of Phe(7) with D-Phe(7) in ACTH(1-17) resulted in the loss of ligand binding and activity. Molecular analysis of MC2R indicated that only mutation of the third transmembrane domain of MC2R resulted in a decrease in D-Phe ACTH binding affinity and potency. Our results suggest that Phe(7) in ACTH plays an important role in ligand selectivity and that the third transmembrane domain of MC2R is crucial for ACTH selectivity and potency.


Asunto(s)
Receptores de Corticotropina/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Citometría de Flujo , Células HEK293 , Humanos , Ligandos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Receptores de Corticotropina/química , Receptores de Corticotropina/genética
16.
Theor Appl Genet ; 129(8): 1595-605, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27170319

RESUMEN

KEY MESSAGE: Predictability estimated through cross-validation approach showed moderate to high level; hence, genomic selection approach holds great potential for biofortification breeding to enhance grain zinc and iron concentrations in wheat. Wheat (Triticum aestivum L.) is a major staple crop, providing 20 % of dietary energy and protein consumption worldwide. It is an important source of mineral micronutrients such as zinc (Zn) and iron (Fe) for resource poor consumers. Genomic selection (GS) approaches have great potential to accelerate development of Fe- and Zn-enriched wheat. Here, we present the results of large-scale genomic and phenotypic data from the HarvestPlus Association Mapping (HPAM) panel consisting of 330 diverse wheat lines to perform genomic predictions for grain Zn (GZnC) and Fe (GFeC) concentrations, thousand-kernel weight (TKW) and days to maturity (DTM) in wheat. The HPAM lines were phenotyped in three different locations in India and Mexico in two successive crop seasons (2011-12 and 2012-13) for GZnC, GFeC, TKW and DTM. The genomic prediction models revealed that the estimated prediction abilities ranged from 0.331 to 0.694 for Zn and from 0.324 to 0.734 for Fe according to different environments, whereas prediction abilities for TKW and DTM were as high as 0.76 and 0.64, respectively, suggesting that GS holds great potential in biofortification breeding to enhance grain Zn and Fe concentrations in bread wheat germplasm.


Asunto(s)
Hierro/análisis , Semillas/anatomía & histología , Triticum/genética , Zinc/análisis , ADN de Plantas/genética , Ambiente , Genoma de Planta , Genotipo , India , México , Modelos Genéticos , Modelos Estadísticos , Fenotipo , Polimorfismo de Nucleótido Simple , Triticum/química
17.
Women Health ; 55(6): 623-45, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25905678

RESUMEN

Psychosocial factors among overweight, obese, and morbidly obese women in Delhi, India were examined. A follow-up survey was conducted of 325 ever-married women aged 20-54 years, systematically selected from 1998-99 National Family Health Survey samples, who were re-interviewed after 4 years in 2003. Information on day-to-day problems, body image dissatisfaction, sexual dissatisfaction, and stigma and discrimination were collected and anthropometric measurements were obtained from women to compute their current body mass index. Three out of four overweight women (BMI between 25 and 29.9 kg/m(2)) were not happy with their body image, compared to four out of five obese women (BMI of 30 kg/m(2) or greater), and almost all (95 percent) morbidly obese women (BMI of 35 kg/m(2) or greater) (p < .0001). It was found that morbidly obese and obese women were five times (adjusted odds ratio [aOR] 5.29, 95% confidence interval [CI] 2.02-13.81, p < .001) and two times (aOR 2.30, 95% CI 1.20-4.42, p < .001), respectively, as likely to report day-to-day problems; twelve times (aOR 11.88, 95% CI 2.62-53.87, p < .001) and three times, respectively, as likely (aOR 2.92, 95% CI 1.45-5.88, p = .001) to report dissatisfaction with body image; and nine times (aOR 9.41, 95% CI 2.96-29.94, p < .001) and three times (aOR 2.93, 95% CI 1.03-8.37, p = .001), respectively, as likely to report stigma and discrimination as overweight women.


Asunto(s)
Imagen Corporal/psicología , Discriminación en Psicología , Obesidad Mórbida/psicología , Obesidad/psicología , Sobrepeso/psicología , Estigma Social , Adolescente , Adulto , Índice de Masa Corporal , Femenino , Estudios de Seguimiento , Humanos , India/epidemiología , Persona de Mediana Edad , Morbilidad , Análisis Multivariante , Obesidad/epidemiología , Obesidad Mórbida/epidemiología , Oportunidad Relativa , Sobrepeso/epidemiología , Encuestas y Cuestionarios , Adulto Joven
18.
Health Care Women Int ; 36(3): 320-41, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-24564448

RESUMEN

We examined the health status of women in relation to their body mass indices and waist-to-hip ratio (WHR) by analyzing data from a follow-up study of 325 women, selected from the Indian National Family Health Survey (NFHS-2/1998-99) Delhi samples, reinterviewed after 4 years (2003). Obese women were five times more likely (OR = 4.87; p <.0001) and women with a higher WHR (> 0.90) were two times more likely (OR = 1.70; p =.050) to perceive their health condition as worse than others. Arthritis, hypertension, and shortness of breath were found to be higher among obese women and women with a high WHR. Healthy lifestyle choices must be promoted to contain the growing burden of obesity-related health problems among Indian women.


Asunto(s)
Índice de Masa Corporal , Obesidad/epidemiología , Relación Cintura-Cadera , Salud de la Mujer/etnología , Adolescente , Adulto , Antropometría , Femenino , Estudios de Seguimiento , Estado de Salud , Encuestas Epidemiológicas , Humanos , Hipertensión/epidemiología , Hipertensión/etnología , India/epidemiología , Estilo de Vida , Modelos Logísticos , Persona de Mediana Edad , Morbilidad , Análisis Multivariante , Obesidad/etnología , Factores de Riesgo , Factores Socioeconómicos , Adulto Joven
19.
Theor Appl Genet ; 127(7): 1643-51, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24865507

RESUMEN

KEY MESSAGE: Ten QTL underlying the accumulation of Zn and Fe in the grain were mapped in a set of RILs bred from the cross Triticum spelta × T. aestivum . Five of these loci (two for Zn and three for Fe) were consistently detected across seven environments. The genetic basis of accumulation in the grain of Zn and Fe was investigated via QTL mapping in a recombinant inbred line (RIL) population bred from a cross between Triticum spelta and T. aestivum. The concentration of the two elements was measured from grain produced in three locations over two consecutive cropping seasons and from a greenhouse trial. The range in Zn and Fe concentration across the RILs was, respectively, 18.8-73.5 and 25.3-59.5 ppm, and the concentrations of the two elements were positively correlated with one another (rp =+0.79). Ten QTL (five each for Zn and Fe accumulation) were detected, mapping to seven different chromosomes. The chromosome 2B and 6A grain Zn QTL were consistently expressed across environments. The proportion of the phenotype explained (PVE) by QZn.bhu-2B was >16 %, and the locus was closely linked to the SNP marker 1101425|F|0, while QZn.bhu-6A (7.0 % PVE) was closely linked to DArT marker 3026160|F|0. Of the five Fe QTL detected, three, all mapping to chromosome 1A were detected in all seven environments. The PVE for QFe.bhu-3B was 26.0 %.


Asunto(s)
Mapeo Cromosómico , Hierro/análisis , Sitios de Carácter Cuantitativo , Triticum/genética , Zinc/análisis , Cromosomas de las Plantas/genética , Cruzamientos Genéticos , ADN de Plantas/genética , Genes de Plantas , Ligamiento Genético , Variación Genética , Fenotipo , Triticum/química
20.
Public Health Nutr ; 17(4): 884-95, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23561825

RESUMEN

OBJECTIVE: We examined the socio-economic differential in the self-perception of body weight, future intention for weight management and actual weight-management behaviour among normal-weight, overweight and obese women in India. DESIGN: A population-based follow-up survey of ever-married women, systematically selected from the second round of the National Family Health Survey (NFHS-2, 1998-99) samples, who were re-interviewed after four years in 2003. SETTING: Information on women's perception about their own weight, intention of weight management and actual weight-management behaviour were collected through personal interview. Anthropometric measurements were obtained from women to compute their current BMI. SUBJECTS: Three hundred and twenty-five ever-married women aged 20-54 years residing in the national capital territory of Delhi in India. RESULTS: Discrepancy between self-perceived body weight and women's actual body weight was reported. One-quarter of overweight women and one in ten obese women perceived themselves as normal weight. Although a majority of overweight and obese women wanted to reduce their weight, a significant proportion of overweight (one in four) and 4 % of obese women also wanted to maintain their weight as it is. Only one in three overweight and one in four obese women were performing any physical activity to reduce their weight. CONCLUSIONS: These findings are important for public health interventions in obesity care. Implementation of health promotion and health education in the community should use effective school education and mass-media programmes to raise awareness of appropriate body weight to combat the growing level of obesity among Indian women.


Asunto(s)
Imagen Corporal , Peso Corporal , Promoción de la Salud , Obesidad/terapia , Sobrepeso/terapia , Programas de Reducción de Peso/métodos , Adulto , Índice de Masa Corporal , Femenino , Estudios de Seguimiento , Encuestas Epidemiológicas , Humanos , India , Modelos Logísticos , Persona de Mediana Edad , Autoimagen , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto Joven
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