RESUMEN
Genetic modification of shoot and root morphology has potential to improve water and nutrient uptake of wheat crops in rainfed environments. Near-isogenic lines (NILs) varying for a tillering inhibition (tin) gene and representing multiple genetic backgrounds were phenotyped in contrasting, controlled environments for shoot and root growth. Leaf area, shoot and root biomass were similar until tillering, whereupon reduced tillering in tin-containing NILs produced reductions of up to 60% in total leaf area and biomass, and increases in total root length of up to 120% and root biomass to 145%. Together, the root-to-shoot ratio increased two-fold with the tin gene. The influence of tin on shoot and root growth was greatest in the cv. Banks genetic background, particularly in the biculm-selected NIL, and was typically strongest in cooler environments. A separate de-tillering study confirmed greater root-to-shoot ratios with regular tiller removal in non-tin-containing genotypes. In validating these observations in a rainfed field study, the tin allele had a negligible effect on seedling growth but was associated with significantly (P<0.05) reduced tiller number (-37%), leaf area index (-26%), and spike number (-35%) to reduce plant biomass (-19%) at anthesis. Root biomass, root-to-shoot ratio at early stem elongation, and root depth at maturity were all increased in tin-containing NILs. Soil water use was slowed in tin-containing NILs, resulting in greater water availability, greater stomatal conductance, cooler canopy temperatures, and maintenance of green leaf area during grain-filling. Together these effects contributed to increases in harvest index and grain yield. In both the controlled and field environments, the tin gene was commonly associated with increased root length and biomass, but the significant influence of genetic background and environment suggests careful assessment of tin-containing progeny in selection for genotypic increases in root growth.
Asunto(s)
Carbono/metabolismo , Proteínas de Plantas/genética , Triticum/fisiología , Agua/metabolismo , Agricultura , Grano Comestible/crecimiento & desarrollo , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Triticum/genética , Triticum/crecimiento & desarrolloRESUMEN
We aim to incorporate deep root traits into future wheat varieties to increase access to stored soil water during grain development, which is twice as valuable for yield as water captured at younger stages. Most root phenotyping efforts have been indirect studies in the laboratory, at young plant stages, or using indirect shoot measures. Here, soil coring to 2 m depth was used across three field environments to directly phenotype deep root traits on grain development (depth, descent rate, density, length, and distribution). Shoot phenotypes at coring included canopy temperature depression, chlorophyll reflectance, and green leaf scoring, with developmental stage, biomass, and yield. Current varieties, and genotypes with breeding histories and plant architectures expected to promote deep roots, were used to maximize identification of variation due to genetics. Variation was observed for deep root traits (e.g. 111.4-178.5cm (60%) for depth; 0.09-0.22cm/°C day (144%) for descent rate) using soil coring in the field environments. There was significant variation for root traits between sites, and variation in the relative performance of genotypes between sites. However, genotypes were identified that performed consistently well or poorly at both sites. Furthermore, high-performing genotypes were statistically superior in root traits than low-performing genotypes or commercial varieties. There was a weak but significant negative correlation between green leaf score (-0.5), CTD (0.45), and rooting depth and a positive correlation for chlorophyll reflectance (0.32). Shoot phenotypes did not predict other root traits. This study suggests that field coring can directly identify variation in deep root traits to speed up selection of genotypes for breeding programmes.
Asunto(s)
Raíces de Plantas/genética , Triticum/genética , Cruzamiento , Variación Genética , Genotipo , Fenotipo , Raíces de Plantas/anatomía & histología , Raíces de Plantas/crecimiento & desarrollo , Suelo , Triticum/anatomía & histología , Triticum/crecimiento & desarrolloRESUMEN
BACKGROUND AND AIMS: Root length and depth determine capture of water and nutrients by plants, and are targets for crop improvement. Here we assess a controlled-environment wheat seedling screen to determine speed, repeatability and relatedness to performance of young and adult plants in the field. METHODS: Recombinant inbred lines (RILs) and diverse genotypes were grown in rolled, moist germination paper in growth cabinets, and primary root number and length were measured when leaf 1 or 2 were fully expanded. For comparison, plants were grown in the field and root systems were harvested at the two-leaf stage with either a shovel or a soil core. From about the four-leaf stage, roots were extracted with a steel coring tube only, placed directly over the plant and pushed to the required depth with a hydraulic ram attached to a tractor. KEY RESULTS: In growth cabinets, repeatability was greatest (r = 0.8, P < 0.01) when the paper was maintained moist and seed weight, pathogens and germination times were controlled. Scanned total root length (slow) was strongly correlated (r = 0.7, P < 0.01) with length of the two longest seminal axile roots measured with a ruler (fast), such that 100-200 genotypes were measured per day. Correlation to field-grown roots at two sites at two leaves was positive and significant within the RILs and cultivars (r = 0.6, P = 0.01), and at one of the two sites at the five-leaf stage within the RILs (r = 0.8, P = 0.05). Measurements made in the field with a shovel or extracted soil cores were fast (5 min per core) and had significant positive correlations to scanner measurements after root washing and cleaning (>2 h per core). Field measurements at two- and five-leaf stages did not correlate with root depth at flowering. CONCLUSIONS: The seedling screen was fast, repeatable and reliable for selecting lines with greater total root length in the young vegetative phase in the field. Lack of significant correlation with reproductive stage root system depth at the field sites used in this study reflected factors not captured in the screen such as time, soil properties, climate variation and plant phenology.
Asunto(s)
Raíces de Plantas/crecimiento & desarrollo , Triticum/crecimiento & desarrollo , Agricultura , Ambiente Controlado , Genotipo , Fenotipo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Raíces de Plantas/genética , Plantas Modificadas Genéticamente , Reproducibilidad de los Resultados , Plantones/genética , Plantones/crecimiento & desarrollo , Suelo , Factores de Tiempo , Triticum/genética , Agua/metabolismoRESUMEN
Wheat yields globally will depend increasingly on good management to conserve rainfall and new varieties that use water efficiently for grain production. Here we propose an approach for developing new varieties to make better use of deep stored water. We focus on water-limited wheat production in the summer-dominant rainfall regions of India and Australia, but the approach is generally applicable to other environments and root-based constraints. Use of stored deep water is valuable because it is more predictable than variable in-season rainfall and can be measured prior to sowing. Further, this moisture is converted into grain with twice the efficiently of in-season rainfall since it is taken up later in crop growth during the grain-filling period when the roots reach deeper layers. We propose that wheat varieties with a deeper root system, a redistribution of branch root density from the surface to depth, and with greater radial hydraulic conductivity at depth would have higher yields in rainfed systems where crops rely on deep water for grain fill. Developing selection systems for mature root system traits is challenging as there are limited high-throughput phenotyping methods for roots in the field, and there is a risk that traits selected in the lab on young plants will not translate into mature root system traits in the field. We give an example of a breeding programme that combines laboratory and field phenotyping with proof of concept evaluation of the trait at the beginning of the selection programme. This would greatly enhance confidence in a high-throughput laboratory or field screen, and avoid investment in screens without yield value. This approach requires careful selection of field sites and years that allow expression of deep roots and increased yield. It also requires careful selection and crossing of germplasm to allow comparison of root expression among genotypes that are similar for other traits, especially flowering time and disease and toxicity resistances. Such a programme with field and laboratory evaluation at the outset will speed up delivery of varieties with improved root systems for higher yield.
Asunto(s)
Cruzamiento , Productos Agrícolas/crecimiento & desarrollo , Raíces de Plantas/crecimiento & desarrollo , Carácter Cuantitativo Heredable , Triticum/crecimiento & desarrollo , Triticum/metabolismo , Agua/metabolismo , Productos Agrícolas/metabolismo , Raíces de Plantas/genéticaRESUMEN
Improvements in water productivity and yield arise from interactions between varieties (G) and their management (M). Most G×M interactions considered by breeders and physiologists focus on in-crop management (e.g. sowing time, plant density, N management). However, opportunities exist to capture more water and use it more effectively that involve judicious management of prior crops and fallows (e.g. crop sequence, weed control, residue management). The dry-land wheat production system of southern Australia, augmented by simulation studies, is used to demonstrate the relative impacts and interactions of a range of pre-crop and in-crop management decisions on water productivity. A specific case study reveals how a novel genetic trait, long coleoptiles that enable deeper sowing, can interact with different management options to increase the water-limited yield of wheat from 1.6 t ha(-1) to 4.5 t ha(-1), reflecting the experience of leading growers. Understanding such interactions will be necessary to capture benefits from new varieties within the farming systems of the future.
Asunto(s)
Agricultura/métodos , Agricultura/organización & administración , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/genética , Eficiencia Organizacional , Ambiente , Agua , Genotipo , Triticum/genética , Triticum/crecimiento & desarrollo , Agua/análisisRESUMEN
AIMS: To evaluate the potential for developing a quality index for a Danish modified atmosphere packaged (MAP) heat-processed and naturally contaminated pork meat product stored at 5 degrees C. METHODS AND RESULTS: The composition of the predominating microflora and changes in contents of tyramine, arginine, organic acids and sensory characteristics were analysed. The microflora was predominated by Lactobacillus sakei, Leuconostoc carnosum and Carnobacterium divergens. The presence of each species varied between products and batches resulting in limited usefulness of the concentrations of these bacteria or their metabolites as indices of quality. Furthermore, the three species differed in their metabolic activities as shown by use of a model meat extract. However, when MAP storage of the processed pork product was followed by aerobic storage then acetic acid showed some potential as a chemical indicator of sensory quality. CONCLUSION: Variation in processing parameters and spoilage microbiota limited the usefulness of concentrations of micro-organisms and their metabolites as indices of spoilage for the studied processed MAP pork product. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study contributes to an understanding of the difficulties experienced in developing quality indices to be used in the control of microbial spoilage of processed MAP meat products.
Asunto(s)
Contaminación de Alimentos , Microbiología de Alimentos , Lactobacillaceae/aislamiento & purificación , Productos de la Carne/microbiología , Animales , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Manipulación de Alimentos/métodos , Productos de la Carne/análisis , Proyectos Piloto , Porcinos , TemperaturaRESUMEN
BACKGROUND: Cold thyroid nodules are common, in particular in iodine-deficient areas, but only a minority of them are malignant requiring surgery. Thyroid peroxidase (TPO) immunostaining of fine-needle aspiration cytology (FNAC) material has proven helpful in diagnosing cells from malignant lesions, but the procedure has its limitations in a routine setting. PURPOSE: To improve diagnosis and reduce surgery rate, the FNAC procedure was replaced by needle core biopsy (NCB), which was routinely stained for TPO by the monoclonal antibody mAb 47. MATERIALS AND METHODS: During a 5-year period 427 consecutive patients with a cold thyroid nodule were evaluated by ultrasound-guided NCB, which had been routinely stained for TPO in an automated immunostainer. Sensitivity and specificity and predictive values of the TPO immunostaining were estimated, based on the final diagnosis obtained from surgical resection. RESULTS: The majority of nodules with benign NCB diagnosis were not surgically removed, and thus a subgroup of 140 operated nodules formed the basis for the calculations. Sensitivity and specificity for benign and malignant lesions were 100% if the oxyphilic variant of adenomas and minimally invasive follicular carcinomas were excluded. By inclusion of these, the values fell to 89% and 97%, respectively. The predictive value of a positive test was 96% and the predictive value of a negative test was 97%. CONCLUSION: TPO immunostaining was found to be a valuable adjunct to morphology in the diagnosis of cold thyroid nodules of the nonoxyphilic type.
Asunto(s)
Inmunohistoquímica , Yoduro Peroxidasa/análisis , Neoplasias de la Tiroides/diagnóstico , Nódulo Tiroideo/diagnóstico , Adenoma/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Carcinoma/diagnóstico , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Coloración y Etiquetado , Neoplasias de la Tiroides/enzimología , Adulto JovenRESUMEN
Sarcoidosis is a systemic chronic granulomatous disease of unknown etiology most commonly affecting young females. The disease was first described in the thyroid gland in 1938. Our patient, a 27-year-old male with known sarcoidosis, was referred to the National University Hospital for acute symptoms of thyrotoxicosis (weight loss of 6 kg, tremor, thyroid enlargement, and tachycardia). Laboratory findings showed suppressed serum thyrotropin (TSH, <0.03 mU/L [0.5-4.20]), increased total thyroxine (T4) (223 nmol/L, [60-140]), and triiodothyronine (T3) (8.5 nmol/L, [1.5-2.7]). Furthermore, Tc-99m pertechnetate scintigraphy disclosed diffuse accumulation of the isotope confirming the diagnosis of Graves' disease. During the next 18 months of antithyroid treatment (thiamazole, Thycapzol) hyperthyroidism was difficult to control, the thyroid gland gradually enlarged, and surgery was recommended. Initially, the patient declined surgery but after an additional 18 months, he accepted surgery. During the 36-month period of antithyroid drug treatment TSH was suppressed (<0.01 mU/L) and T3 often elevated despite high doses of thiamazole. Total thyroidectomy was performed, and histologic examination of the removed thyroid tissue confirmed the diagnosis of Graves' disease and also the presence of sarcoid granuloma and metastatic papillary adenocarcinoma with spread to neck lymph nodes. Four months later, a modified radical neck dissection was performed with removal of neck lymph nodes followed by external radiation therapy (2 Gy x 32 fractions to the neck). The concomitant presence of sarcoidosis, papillary carcinoma, and Graves' disease in a thyroid gland, to our knowledge, has not previously been described in the literature.
Asunto(s)
Carcinoma Papilar/diagnóstico , Granuloma/diagnóstico , Enfermedad de Graves/diagnóstico , Sarcoidosis/diagnóstico , Enfermedades de la Tiroides/diagnóstico , Neoplasias de la Tiroides/diagnóstico , Adulto , Antitiroideos/uso terapéutico , Carcinoma Papilar/patología , Carcinoma Papilar/radioterapia , Carcinoma Papilar/cirugía , Granuloma/patología , Enfermedad de Graves/tratamiento farmacológico , Enfermedad de Graves/patología , Humanos , Metástasis Linfática , Masculino , Metimazol/uso terapéutico , Sarcoidosis/patología , Enfermedades de la Tiroides/patología , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/cirugía , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangreRESUMEN
The effect of canola (Brassica napus) as a crop suppressive to Pratylenchus neglectus is in part due to the release of nematicidal isothiocyanates, particularly 2-phenylethyl isothiocyanate, from degrading root tissues. However, many cultivars of canola are relatively susceptible to P. neglectus and will fail to reduce soil populations of the nematode. A survey of B. napus accessions and closely related species revealed limited scope to decrease the susceptibility of canola through conventional intercrossing. Susceptibility to P. neglectus was not related to the total glucosinolate levels, but there were signifi- cant, negative correlations (r = -0.619, -0.517; P < 0.001) between root levels of 2-phenylethyl glucosinolate (isothiocyanate precursor) and plant susceptibility to P. neglectus: plants containing more than a certain threshold level of 2-phenylethyl glucosinolate showed reduced susceptibility to the nematode. Selection for high root levels of 2-phenylethyl glucosinolate should reduce the susceptibility of the plants during the growing season while also increasing the nematicidal impact of the degrading root tissues, thereby improving the suppressive benefits of the crop when used in rotation with cereals.
RESUMEN
308 patients with intraoral carcinomas were treated in the Finsen Institute, Copenhagen, from 1978 to 1982. As primary treatment, 73% of the patients had radiotherapy alone, 5% had operations alone, and 14% had combined treatment. After first recurrences, 45% of 204 patients were operated on. This treatment strategy kept 40% of all 308 patients free of disease for at least 3.5 years or until death. Fifty-eight percent of all 308 patients died of their oral carcinomas. The present study shows that tumor size, lymph node involvement, and total tumor stage are important prognostic factors. Old and new treatment strategies are discussed and more use of operations using modern reconstructive techniques followed by radiotherapy is recommended.
Asunto(s)
Carcinoma de Células Escamosas/terapia , Neoplasias de la Boca/terapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/mortalidad , Estadificación de Neoplasias , Estudios ProspectivosRESUMEN
Eighty-eight patients with thyroid malignancy seen at the Rigshospital, Copenhagen during the period 1.5.1989-1.5.1994 were retrospectively studied. There were 64 females and 24 males. The average age was 54 years. Seventy-nine patients were operated (six with subtotal and 73 with total thyroidectomy). Thirty-six (46%) had had previous thyroid operations and 12 of these patients had preoperative fine-needle aspiration biopsies performed. The second operation thyroidectomy specimen contained carcinoma in 14 (39%) of the 36 patients. Forty-nine patients (62%) had different types of modified neck dissection performed under the operation and 31 (39%) of the operated patients had lymph-node-metastases. Among the patients who were operated at the department there were no accidental permanent recurrent nerve paralysis. Among the 36 patients who were operated at other departments there were four (11%) accidental recurrent nerve paralysis from the primary operation. Twenty (25%) of the 79 operated patients developed permanent hypoparathyroidism.
Asunto(s)
Carcinoma/cirugía , Complicaciones Posoperatorias/diagnóstico , Neoplasias de la Tiroides/cirugía , Tiroidectomía/efectos adversos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Parálisis de los Pliegues Vocales/diagnóstico , Parálisis de los Pliegues Vocales/etiologíaRESUMEN
INTRODUCTION: Two new methods of reconstructing the proximal oesophagus after resection of cancer in the larynx, hypopharynx, or proximal oesophagus are examined. MATERIAL AND METHOD: Between 1991 and 1996, 12 patients were operated on after initial irradiation. The reconstructions were done by a microsurgical technique, with eight jejunum transplants and four tubulated radial forearm flaps. The records were reviewed retrospectively. RESULTS: The patients were hospitalised for about a month and were able to swallow soft food three weeks after the operation. Most patients achieved pain palliation and a good swallowing function for a period of three to more than 24 months, until relapse. All patients except two died between five and 21 months after the operation. DISCUSSION AND CONCLUSION: Both techniques give an acceptable swallowing function until relapse. The size of the defect indicates the choice of flap. They are also suitable in such situations as complex fistula formation, congenital atresia, and the after-effects of corrosion.
Asunto(s)
Neoplasias Esofágicas/cirugía , Esofagoscopía/métodos , Neoplasias Hipofaríngeas/cirugía , Neoplasias Laríngeas/cirugía , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Anciano , Neoplasias Esofágicas/radioterapia , Esofagectomía , Femenino , Humanos , Neoplasias Hipofaríngeas/radioterapia , Yeyuno/trasplante , Neoplasias Laríngeas/radioterapia , Laringectomía , Masculino , Persona de Mediana Edad , Faringectomía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/cirugía , Arteria Radial/trasplante , Estudios Retrospectivos , Trasplante de PielRESUMEN
Study of patients with oral carcinomas from the Finsen Institute in a five-year period, shows the survival to be significantly correlated to the tumour stage on referral. In order to improve the prognosis for these patients, earlier diagnosis and earlier referral for treatment to the oncological centre are necessary.
Asunto(s)
Neoplasias de la Boca/diagnóstico , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Factores de TiempoRESUMEN
Invasive fibrous thyroiditis (Riedel's goitre) is a rare condition of an unknown aetiology. The condition was first described by Riedel in 1883. In 1904 Hashimoto described another condition of invasive fibrous thyroiditis. Since then it has been discussed if Hashimoto's thyroiditis and Riedel's goitre were one disease in different states or two different diseases. Hashimoto's thyroiditis is known to have an autoimmune aetiology and it can be seen together with pernicious anaemia. Co-existence of Riedel's goitre and pernicious anaemia has never been reported. The patient mentioned had both Riedel's goitre and pernicious anaemia, and was first treated with subtotal thyroidectomy, relapsed after one year and consequently received steroids. Such coexistence and the very good effect of steroids could be explained on the basis of Hashimoto's and Riedel's thyroiditis being one condition in different states and with an autoimmune aetiology. It is recommended that patients with Riedel's goitre are postoperatively treated with steroids.
Asunto(s)
Tiroiditis Autoinmune , Tiroiditis , Diagnóstico Diferencial , Femenino , Fibrosis , Humanos , Persona de Mediana Edad , Cuidados Posoperatorios , Prednisolona/uso terapéutico , Pronóstico , Glándula Tiroides/diagnóstico por imagen , Glándula Tiroides/patología , Tiroiditis/diagnóstico , Tiroiditis/tratamiento farmacológico , Tiroiditis/cirugía , Tiroiditis Autoinmune/diagnóstico , Tiroiditis Autoinmune/tratamiento farmacológico , Tiroiditis Autoinmune/cirugía , Tomografía Computarizada por Rayos XRESUMEN
INTRODUCTION: The chance of malignancy in scintigraphically cold thyroid nodules is 2-24%. Differentiation between malignant and benign cytology is difficult. The aim of this study was to evaluate the ability of immunostaining (MoAB47--raised against thyroid peroxidase (TPO)) to differentiate between malignant and benign cells taken from cold thyroid nodules by fine needle aspiration biopsy (FNAB) in order to reduce the number of unnecessary thyroid operations. MATERIALS AND METHODS: One hundred and eighty-one patients (150 female) with a scintigraphically cold, solitary thyroid nodule were entered between 1993 and 1996. Fifty-seven were excluded for various reasons. Material removed by FNAB was stained with MoAB47 and routine staining. Staining of 80% or more of the cells was considered benign, less than 80% was considered malignant. Routine staining of operatively removed material was used as the final diagnosis. RESULTS: A pattern with negative TPO staining was found in all lesions that were subsequently proved to be malignant. In all but one, the lesions subsequently diagnosed as being benign stained positive for TPO. The sensitivity and specificity were respectively 1.0 and 0.99. CONCLUSION: TPO immunostaining of material removed by FNAB is a powerful tool in the differentiation between benign and malignant tumours.