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1.
J Laryngol Otol ; 136(3): 229-236, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34465402

RESUMEN

OBJECTIVE: This study aimed to compare the effectiveness of pharmacological therapy with and without direct maxillary sinus saline irrigation for the management of chronic rhinosinusitis without polyps. METHODS: In this prospective randomised controlled trial, 39 non-operated patients were randomly assigned to be treated with direct maxillary sinus saline irrigation in conjunction with systemic antibiotics and topical sprays (n = 24) or with pharmacological therapy alone (n = 15). Endoscopy, Sino-Nasal Outcome Test and Lund-MacKay computed tomography scores were obtained before, six weeks after and one to two years after treatment. RESULTS: Post-treatment Lund-Mackay computed tomography scores were significantly improved in both cohorts, with no inter-cohort difference identified. Post-treatment nasal endoscopy scores were significantly improved in the study group but were similar to those measured in the control group. The Sino-Nasal Outcome Test-20 results showed improvement in both cohorts, with no difference between treatment arms. CONCLUSION: Maxillary sinus puncture and irrigation with saline, combined with pharmacological treatment improves endoscopic findings in patients with chronic rhinosinusitis without polyps, but has no beneficial effect on symptoms and imaging findings over conservative treatment alone.


Asunto(s)
Antibacterianos/uso terapéutico , Seno Maxilar , Descongestionantes Nasales/uso terapéutico , Lavado Nasal (Proceso) , Rinitis/terapia , Sinusitis/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rociadores Nasales , Estudios Prospectivos , Solución Salina/uso terapéutico , Resultado del Tratamiento , Adulto Joven
2.
Appl Magn Reson ; 52(1): 61-80, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33776217

RESUMEN

A probability distribution of rate constants contained within an exponential-like saturation recovery (SR) electron paramagnetic resonance signal can be constructed using stretched exponential function fitting parameters. Previously (Stein et al. Appl. Magn. Reson. 2019.), application of this method was limited to the case where only one relaxation process, namely spin-lattice relaxations due to the rotational diffusion of the spin labels in the intact eye-lens membranes, contributed to an exponential-like SR signal. These conditions were achieved for thoroughly deoxygenated samples. Here, the case is described where the second relaxation process, namely Heisenberg exchange between the spin label and molecular oxygen that occurs during bimolecular collisions, contributes to the decay of SR signals. We have further developed the theory for application of stretched exponential function to analyze SR signals involving these two processes. This new approach allows separation of stretched exponential parameters, namely characteristic stretched rates and heterogeneity parameters for both processes. Knowing these parameters allowed us to separately construct the probability distributions of spin-lattice relaxation rates determined by the rotational diffusion of spin labels and the distribution of relaxations induced strictly by collisions with molecular oxygen. The later distribution is determined by the distribution of oxygen diffusion concentration products within the membrane, which forms a sensitive new way to describe membrane fluidity and heterogeneity. This method was validated in silico and by fitting SR signals from spin-labeled intact nuclear fiber cell plasma membranes extracted from porcine eye lenses equilibrated with different fractions of air.

3.
J Geophys Res Planets ; 125(9): e2019JE006289, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32999802

RESUMEN

The Mars Science Laboratory (MSL) Curiosity rover is exploring the Murray formation, a sequence of heterolithic mudstones and sandstones recording fluvial deltaic and lake deposits that comprise over 350 m of sedimentary strata within Gale crater. We examine >4,500 Murray formation bedrock points, employing recent laboratory calibrations for ChemCam laser-induced breakdown spectroscopy H measurements at millimeter scale. Bedrock in the Murray formation has an interquartile range of 2.3-3.1 wt.% H2O, similar to measurements using the Dynamic Albedo of Neutrons and Sample Analysis at Mars instruments. However, specific stratigraphic intervals include high H targets (6-18 wt.% H2O) correlated with Si, Mg, Ca, Mn, or Fe, indicating units with opal, hydrated Mg sulfates, hydrated Ca sulfates, Mn-enriched units, and akageneite or other iron oxyhydroxides, respectively. One stratigraphic interval with higher hydrogen is the Sutton Island unit and Blunts Point unit contact, where higher hydrogen is associated with Fe-rich, Ca-rich, and Mg-rich points. A second interval with higher hydrogen occurs in the Vera Rubin ridge portion of the Murray formation, where higher hydrogen is associated with Fe-rich, Ca-rich, and Si-rich points. We also observe trends in the H signal with grain size, separate from chemical variation, whereby coarser-grained rocks have higher hydrogen. Variability in the hydrogen content of rocks points to a history of water-rock interaction at Gale crater that included changes in lake water chemistry during Murray formation deposition and multiple subsequent groundwater episodes.

4.
J Geophys Res Planets ; 125(12): e2020JE006527, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33520561

RESUMEN

This paper provides an overview of the Curiosity rover's exploration at Vera Rubin ridge (VRR) and summarizes the science results. VRR is a distinct geomorphic feature on lower Aeolis Mons (informally known as Mount Sharp) that was identified in orbital data based on its distinct texture, topographic expression, and association with a hematite spectral signature. Curiosity conducted extensive remote sensing observations, acquired data on dozens of contact science targets, and drilled three outcrop samples from the ridge, as well as one outcrop sample immediately below the ridge. Our observations indicate that strata composing VRR were deposited in a predominantly lacustrine setting and are part of the Murray formation. The rocks within the ridge are chemically in family with underlying Murray formation strata. Red hematite is dispersed throughout much of the VRR bedrock, and this is the source of the orbital spectral detection. Gray hematite is also present in isolated, gray-colored patches concentrated toward the upper elevations of VRR, and these gray patches also contain small, dark Fe-rich nodules. We propose that VRR formed when diagenetic event(s) preferentially hardened rocks, which were subsequently eroded into a ridge by wind. Diagenesis also led to enhanced crystallization and/or cementation that deepened the ferric-related spectral absorptions on the ridge, which helped make them readily distinguishable from orbit. Results add to existing evidence of protracted aqueous environments at Gale crater and give new insight into how diagenesis shaped Mars' rock record.

5.
Haemophilia ; 24(4): 634-640, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29608015

RESUMEN

INTRODUCTION: Drugs targeting factor XI (FXI) shows promising results in reducing postoperative VTE. Recently, researchers have shown that FXI knockout mice had a worse outcome when infected with pathogens for pneumonia, raising concerns about the safety of these drugs. AIM: To investigate the effect of FXI deficiency on the incidence of pneumonia and outcomes of pneumonia in humans. METHODS: Using the computerized database of the largest healthcare provider in Israel, we identified adults who were tested for FXI activity between January of 2002 and December of 2014 (n = 10 193). Patients were followed up until December of 2016 for the occurrence of pneumonia and pneumonia requiring hospitalization as a proxy of severe pneumonia. RESULTS: A total of 8958 (87.9%) had normal FXI activity, 804 (7.9%) had partial deficiency and 431 (4.2%) had severe deficiency; 722 individuals had pneumonia during 70 881 person-years of follow-up (incidence rate: 10.2 per 1000 person-years). Compared to those with normal FXI activity, the adjusted HR for pneumonia was 0.87 (95% CI, 0.67-1.14), and 0.95 (0.69-1.30) for those with partial and severe FXI deficiency, respectively. Overall, 256 individuals were hospitalized for pneumonia during 72 209 person-years of follow-up (incidence rate: 3.5 per 1000 person-years). The corresponding HR for severe pneumonia was 1.0 (0.70-1.48) and 0.86 (0.53-1.40) in those with partial and severe FXI deficiency, respectively. FXI deficiency was not significantly associated with 30-day and 90-day mortality among patients with pneumonia. CONCLUSION: FXI deficiency was not associated with an increased risk of pneumonia, pneumonia severity or short-term mortality among patients with pneumonia.


Asunto(s)
Deficiencia del Factor XI/complicaciones , Neumonía/complicaciones , Neumonía/mortalidad , Adulto , Femenino , Humanos , Inmunidad Innata , Masculino , Persona de Mediana Edad , Neumonía/inmunología , Riesgo , Análisis de Supervivencia
7.
Science ; 356(6341)2017 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-28572336

RESUMEN

In 2012, NASA's Curiosity rover landed on Mars to assess its potential as a habitat for past life and investigate the paleoclimate record preserved by sedimentary rocks inside the ~150-kilometer-diameter Gale impact crater. Geological reconstructions from Curiosity rover data have revealed an ancient, habitable lake environment fed by rivers draining into the crater. We synthesize geochemical and mineralogical data from lake-bed mudstones collected during the first 1300 martian solar days of rover operations in Gale. We present evidence for lake redox stratification, established by depth-dependent variations in atmospheric oxidant and dissolved-solute concentrations. Paleoclimate proxy data indicate that a transition from colder to warmer climate conditions is preserved in the stratigraphy. Finally, a late phase of geochemical modification by saline fluids is recognized.


Asunto(s)
Sedimentos Geológicos/química , Lagos , Marte , Oxidación-Reducción
9.
J Geophys Res Planets ; 122(12): 2544-2573, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29497590

RESUMEN

The Mars Science Laboratory rover Curiosity visited two active wind-blown sand dunes within Gale crater, Mars, which provided the first ground-based opportunity to compare Martian and terrestrial eolian dune sedimentary processes and study a modern analog for the Martian eolian rock record. Orbital and rover images of these dunes reveal terrestrial-like and uniquely Martian processes. The presence of grainfall, grainflow, and impact ripples resembled terrestrial dunes. Impact ripples were present on all dune slopes and had a size and shape similar to their terrestrial counterpart. Grainfall and grainflow occurred on dune and large-ripple lee slopes. Lee slopes were ~29° where grainflows were present and ~33° where grainfall was present. These slopes are interpreted as the dynamic and static angles of repose, respectively. Grain size measured on an undisturbed impact ripple ranges between 50 µm and 350 µm with an intermediate axis mean size of 113 µm (median: 103 µm). Dissimilar to dune eolian processes on Earth, large, meter-scale ripples were present on all dune slopes. Large ripples had nearly symmetric to strongly asymmetric topographic profiles and heights ranging between 12 cm and 28 cm. The composite observations of the modern sedimentary processes highlight that the Martian eolian rock record is likely different from its terrestrial counterpart because of the large ripples, which are expected to engender a unique scale of cross stratification. More broadly, however, in the Bagnold Dune Field as on Earth, dune-field pattern dynamics and basin-scale boundary conditions will dictate the style and distribution of sedimentary processes.

10.
J Geophys Res Planets ; 122(12): 2510-2543, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29497589

RESUMEN

The Mars Science Laboratory Curiosity rover performed coordinated measurements to examine the textures and compositions of aeolian sands in the active Bagnold dune field. The Bagnold sands are rounded to subrounded, very fine to medium sized (~45-500 µm) with ≥6 distinct grain colors. In contrast to sands examined by Curiosity in a dust-covered, inactive bedform called Rocknest and soils at other landing sites, Bagnold sands are darker, less red, better sorted, have fewer silt-sized or smaller grains, and show no evidence for cohesion. Nevertheless, Bagnold mineralogy and Rocknest mineralogy are similar with plagioclase, olivine, and pyroxenes in similar proportions comprising >90% of crystalline phases, along with a substantial amorphous component (35% ± 15%). Yet Bagnold and Rocknest bulk chemistry differ. Bagnold sands are Si enriched relative to other soils at Gale crater, and H2O, S, and Cl are lower relative to all previously measured Martian soils and most Gale crater rocks. Mg, Ni, Fe, and Mn are enriched in the coarse-sieved fraction of Bagnold sands, corroborated by visible/near-infrared spectra that suggest enrichment of olivine. Collectively, patterns in major element chemistry and volatile release data indicate two distinctive volatile reservoirs in Martian soils: (1) amorphous components in the sand-sized fraction (represented by Bagnold) that are Si-enriched, hydroxylated alteration products and/or H2O- or OH-bearing impact or volcanic glasses and (2) amorphous components in the fine fraction (<40 µm; represented by Rocknest and other bright soils) that are Fe, S, and Cl enriched with low Si and adsorbed and structural H2O.

11.
Sleep Disord ; 2016: 8032528, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27660727

RESUMEN

Objectives. To quantify and characterize hypnotics consumption habits among adult patients insured by Clalit Health Services (CHS), the largest health care provider in Israel, in 2000 and 2010. Methods. A retrospective analysis of CHS computerized pharmacy records. Data were collected for all patients over the age of 18 years who were prescribed hypnotics in 2000 and in 2010. Results. Sleep medications were consumed by 8.7% of the adult CHS population in 2000 and by 9.6% in 2010. About one-quarter of consumers were treated for more than 6 months in both years. Multiple sleeping drugs were consumed more often in 2010 (45.2%) than a decade before (22%). While in 2000 benzodiazepines accounted for 84.5% of hypnotics, in 2010 this was reduced to 73.7% (p < 0.05). Of all patients treated for longer than 6 months only 11% in 2000 and 9% in 2010 required a dose escalation suggesting the absence of tolerance. Conclusions. Nine percent of the Israeli population consumes hypnotics. There is a major increase in prescription of combination of medications between 2000 and 2010, with an increase in Z class medications use and reduction in benzodiazepines. Most patients chronically treated did not escalate dosage, suggesting the absence of tolerance.

12.
Water Sci Technol ; 72(3): 371-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26204068

RESUMEN

For chemical industries, fresh water availability is a pre-requisite for sustainable operation. However, in many delta areas around the world, fresh water is scarce. Therefore, the E4 Water project (www.e4water.eu) comprises a case study at the Dow site in Terneuzen, The Netherlands, which is designed to develop commercial applications for mild desalination of brackish raw water streams from various origins to enable reuse in industry or agriculture. This study describes an effective two-stage work process, which was used to narrow down a broad spectrum of desalination technologies to a selection of the most promising techniques for a demonstration pilot at 2-4 m³/hour. Through literature study, laboratory experiments and multi-criteria analysis, nanofiltration and electrodialysis reversal were selected, both having the potential to attain the objectives of E4Water at full scale.


Asunto(s)
Salinidad , Cloruro de Sodio/química , Aguas Residuales/química , Purificación del Agua/métodos , Países Bajos
13.
Postgrad Med ; 126(3): 231-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24918807

RESUMEN

OBJECTIVE: This study investigated the impact of the hepatic hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) on the leptin-induced human umbilical vein endothelial (HUVE) cell proliferation, migration, and capillary-like tube formation. METHODS: The HUVE cells were isolated and cultured, and stimulated with leptin, statins (cerivastatin, fluvastatin, simvastatin), mevalonate, farnesyl pyrophosphate, geranylgeranyl pyrophosphate, or methyl-ß-cyclodextrin. The endothelial cell proliferation was assessed using the Neubauer counting chamber. The migration of HUVE cells was examined with the planar migration assay. In vitro capillary sprouting was quantified by measuring the sprout length, number, and cumulative sprout length. RESULTS: The HMG-CoA reductase inhibitors significantly reduced leptin-induced proliferation and migration, which was reversed by mevalonate. Further, the inhibitory effect of the statins on leptin-induced migration was shown to be modulated by the prenylation of farnesyl pyrophosphate and geranylgeranyl pyrophosphate. Although stimulation with a leptin showed no significant effect, a marked increase in capillary-like tube formation was observed with a joint stimulation with HMG-CoA reductase inhibitors. Although statins caused inhibition of proliferation and migration, the same dose of the agents amplified the selective growth of capillary-like tube formation. Membranous cholesterol depletion by methyl-ß-cyclodextrin showed a weaker effect compared with statins. CONCLUSION: Through modulation of prenylation, leptin-induced pro-atherosclerotic events including proliferation and migration were inhibited by HMG-CoA reductase inhibitors.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Endoteliales/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Leptina/farmacología , Relación Dosis-Respuesta a Droga , Farnesiltransferasa/farmacología , Humanos , Ácido Mevalónico/farmacología , Pirofosfatasas/farmacología , Venas Umbilicales , beta-Ciclodextrinas/farmacología
14.
Cytogenet Genome Res ; 142(1): 66-78, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24335088

RESUMEN

Specific localization of large genomic fragments by fluorescence in situ hybridization (FISH) is challenging in large- genome plant species due to the high content of repetitive sequences. We report the automated work flow (Kmasker) for in silico extraction of unique genomic sequences of large genomic fragments suitable for FISH in barley. This method can be widely used for the integration of genetic and cytogenetic maps in plants and other species with large and complex genomes if the probe sequence (e.g. BACs, sequence contigs) and a low coverage (8-fold) of unassembled sequences of the species of interest are available. Kmasker has been made publicly available as a web tool at http://webblast.ipk-gatersleben.de/kmasker.


Asunto(s)
Simulación por Computador , Sondas de ADN , ADN de Plantas/genética , Genoma de Planta , Hordeum/genética , Hibridación Fluorescente in Situ/métodos , Modelos Genéticos , Secuencias Repetitivas de Ácidos Nucleicos , Programas Informáticos , Algoritmos , Mapeo Cromosómico , Cromosomas Artificiales Bacterianos , Cromosomas de las Plantas/genética , ADN Ribosómico/genética , Dosificación de Gen , Genes de Plantas , Haploidia , ARN de Planta/genética , ARN Ribosómico 5S/genética , Análisis de Secuencia de ADN
15.
Chromosome Res ; 21(8): 739-51, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24026304

RESUMEN

Fluorescence in situ hybridization (FISH) is a widely used method to localize DNA sequences on chromosomes. Out of the many uses, FISH facilitates construction of physical maps by ordering contigs of large-insert DNA clones, typically bacterial artificial chromosome (BAC) and establishing their orientation. This is important in genomic regions with low recombination frequency where genetic maps suffer from poor resolution. While BAC clones can be mapped directly by FISH in plants with small genomes, excess of repetitive DNA hampers this application in species with large genomes. Mapping single-copy sequences such as complementary DNA (cDNA) is an attractive alternative. Unfortunately, localization of single-copy sequences shorter than 10 kb remains a challenging task in plants. Here, we present a highly efficient FISH technique that enables unambiguous localization of single copy genes. We demonstrated its utility by mapping 13 out of 15 full-length cDNAs of variable length (2,127-3,400 bp), which were genetically defined to centromeric and pericentromeric regions of barley chromosome 7H. We showed that a region of 1.2 cM (0.7 %) on genetic map represented more than 40 % of the physical length of the chromosome. Surprisingly, all cDNA probes occasionally revealed hybridization signals on other chromosomes, indicating the presence of partially homologous sequences. We confirmed the order of 10 cDNA clones and suggested a different position for three cDNAs as compared to published genetic order. These results underline the need for alternative approaches such as FISH, which can resolve the order of markers in genomic regions where genetic mapping fails.


Asunto(s)
Mapeo Contig/métodos , Genoma de Planta , Hordeum/genética , Hibridación Fluorescente in Situ/métodos , Cromosomas Artificiales Bacterianos , Cromosomas de las Plantas/genética , Clonación Molecular , ADN de Plantas/genética , Marcadores Genéticos , Hordeum/química , Hibridación de Ácido Nucleico , Análisis de Secuencia de ADN
16.
Funct Integr Genomics ; 12(4): 573-83, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23161406

RESUMEN

The genomic resources of small grain cereals that include some of the most important crop species such as wheat, barley, and rye are attaining a level of completion that now is contributing to new structural and functional studies as well as refining molecular marker development and mapping strategies for increasing the efficiency of breeding processes. The integration of new efforts to obtain reference sequences in bread wheat and barley, in particular, is accelerating the acquisition and interpretation of genome-level analyses in both of these major crops.


Asunto(s)
Genómica , Plantas Modificadas Genéticamente , Triticum/genética , Mapeo Físico de Cromosoma
17.
J Endocrinol Invest ; 35(5): 464-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21952495

RESUMEN

BACKGROUND: No increased mortality has been reported in patients with thyroid papillary microcarcinoma (PMC); however, neck recurrences and distant metastases have been described. In this study, we compare patients' outcomes after total thyroidectomy vs hemithyroidectomy for treatment of thyroid PMC. METHODS: Two hundred and ninety-three patients from two major medical centers in Israel were included. The mean follow-up period was 7.2±6.8 yr. RESULTS: Total thyroidectomy was performed in 214 patients and hemithyroidectomy in 79 patients. Mean tumor size was 6.3±3 mm. Lymph-node (LN) metastases and extraglandular extension were more frequent in the total thyroidectomy group than in the hemithyroidectomy group, 24.8% vs 1.3% (p<0.001) and 11.7% vs 3.8% (p=0.042), respectively. The cumulative incidence of recurrence at the end of follow-up was 13.2% in the total thyroidectomy group and 14.3% in the hemithyroidectomy group (p=ns). The incidence of recurrence was higher in patients with LN involvement in both groups. Considering low risk patients only (monofocal tumors, no LN involvement, no extraglandular extension; no.=63 in the total thyroidectomy group vs no.=60 in the hemithyroidectomy group) neck recurrence was found in 10% of patients in the hemithyroidectomy group but none in the total thyroidectomy group. In the hemithyroidectomy group, all locoregional recurrences were diagnosed using ultrasonography, compared to 47.6% in the total thyroidectomy group. CONCLUSION: For patients with monofocal disease within the thyroid gland and no LN involvement, hemithyroidectomy can be considered an option, bearing in mind a higher risk for recurrence. For all other patients with PMC, we propose total thyroidectomy as initial treatment.


Asunto(s)
Adenocarcinoma Papilar/cirugía , Recurrencia Local de Neoplasia/cirugía , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Adenocarcinoma Papilar/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Israel , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/diagnóstico , Pronóstico , Estudios Prospectivos , Neoplasias de la Tiroides/diagnóstico , Adulto Joven
18.
Nanotechnology ; 22(13): 135601, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21343643

RESUMEN

Nanocrystalline bulk materials are desirable for many applications as they combine mechanical strength and specific electronic transport properties. Our bottom-up approach starts with tailored nanoparticles. Compaction and thermal treatment are crucial, but usually the final stage sintering is accompanied by rapid grain growth which spoils nanocrystallinity. For electrically conducting nanoparticles, field activated sintering techniques overcome this problem. Small grain sizes have been maintained in spite of consolidation. Nevertheless, the underlying principles, which are of high practical importance, have not been fully elucidated yet. In this combined experimental and theoretical work, we show how the developing microstructure during sintering correlates with the percolation paths of the current through the powder using highly doped silicon nanoparticles as a model system. It is possible to achieve a nanocrystalline bulk material and a homogeneous microstructure. For this, not only the generation of current paths due to compaction, but also the disintegration due to Joule heating is required. The observed density fluctuations on the micrometer scale are attributed to the heat profile of the simulated powder networks.

19.
Plant Biol (Stuttg) ; 12(6): 871-82, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21040302

RESUMEN

In an attempt to shed light on the role of root systems in differential responses of wheat genotypes to long-term water limitation, transcriptional differences between two wheat genotypes (Triticum aestivum L., cv. Plainsman V and landrace Kobomugi) were identified during adaptation to moderate water stress at the tillering stage. Differences in organ sizes, water-use efficiency and seed production were detected in plants grown in soil, and root functions were characterised by expression profiling. The molecular genetic background of the behaviour of the two genotypes during this stress was revealed using a cDNA macroarray for transcript profiling of the roots. During a 4-week period of moderate water deficit, a set of up-regulated genes displaying transiently increased expression was identified in young plantlets, mostly in the second week in the roots of Kobomugi, while transcript levels remained constantly high in roots of Plainsman V. These genes encode proteins with various functions, such as transport, protein metabolism, osmoprotectant biosynthesis, cell wall biogenesis and detoxification, and also regulatory proteins. Oxidoreductases, peroxidases and cell wall-related genes were induced significantly only in Plainsman V, while induction of stress- and defence-related genes was more pronounced in Kobomugi. Real-time qPCR analysis of selected members of the glutathione S-transferase gene family revealed differences in regulation of family members in the two genotypes and confirmed the macroarray results. The TaGSTZ gene was stress-activated only in the roots of Kobomugi.


Asunto(s)
Sequías , Genotipo , Raíces de Plantas/fisiología , Triticum/genética , Agua/fisiología , Análisis por Conglomerados , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Análisis de Secuencia por Matrices de Oligonucleótidos , Raíces de Plantas/genética , ARN de Planta/genética , Triticum/fisiología
20.
Mol Ecol ; 18(7): 1523-36, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19368652

RESUMEN

In this study, we present the genetic analysis of a new collection of wild barley (Hordeum spontaneum) using 42 simple sequence repeat (SSR) markers that represent the seven chromosomes. The Barley1K (B1K) infrastructure consists of 1020 accessions collected in a hierarchical sampling mode (HSM) from 51 sites across Israel and represents the wide adaptive niche of the modern barley's ancestor. According to the genetic structure analysis, the sampled sites can be divided into seven groups, and sampled microsites located on opposing slopes or in different soil types did not show significant genetic differentiation. Although the genetic analysis indicates a simple isolation-by-distance model among the populations, examination of the genetic populations' structure with abiotic parameters in an ordination analysis revealed that the combination of elevation, mid-day temperature and rainfall explains a high proportion of the variance in the principal components analysis. Our findings demonstrate that the current populations have therefore been shaped and distinguished by non-selective forces such as migration; however, we suggest that aridity and temperature gradients played major roles as selective forces in the adaptation of wild barley in this part of the Fertile Crescent. This unique collection is a prelude for the investigation of the molecular basis underlying plant adaptation and responsiveness to harsh environments.


Asunto(s)
Genética de Población , Hordeum/genética , Lluvia , Temperatura , Adaptación Fisiológica/genética , Altitud , ADN de Plantas/genética , Genes de Plantas , Marcadores Genéticos , Variación Genética , Israel , Repeticiones de Microsatélite , Modelos Genéticos , Análisis de Componente Principal
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