RESUMEN

To create a framework for genetic dissection of hexaploid triticale, six populations of doubled haploid (DH) lines were developed from pairwise hybrids of high-yielding winter triticale cultivars. The six populations comprise between 97 and 231 genotyped DH lines each, totaling 957 DH lines. A consensus genetic map spans 4593.9 cM is composed of 1576 unique DArT markers. The maps reveal several structural rearrangements in triticale genomes. In preliminary tests of the populations and maps, markers specific to wheat segments of the engineered rye chromosome 1R (RM1B) were identified. Example QTL mapping of days to heading in cv. Krakowiak revealed loci on chromosomes 2BL and 2R responsible for extended vernalization requirement, and candidate genes were identified. The material is available to all parties interested in triticale genetics.

RESUMEN

The genetic programs that direct formation of the treelike branching structures of two animal organs have begun to be elucidated. In both the developing Drosophila tracheal (respiratory) system and mammalian lung, a fibroblast growth factor (FGF) signaling pathway is reiteratively used to pattern successive rounds of branching. The initial pattern of signaling appears to be established by early, more global embryonic patterning systems. The FGF pathway is then modified at each stage of branching by genetic feedback controls and other signals to give distinct branching outcomes. The reiterative use of a signaling pathway by both insects and mammals suggests a general scheme for patterning branching morphogenesis.

Asunto(s)

Tipificación del Cuerpo/genética , Drosophila/embriología , Factores de Crecimiento de Fibroblastos/fisiología , Pulmón/embriología , Animales , Drosophila/anatomía & histología , Drosophila/genética , Epitelio/metabolismo , Factores de Crecimiento de Fibroblastos/genética , Regulación del Desarrollo de la Expresión Génica , Larva/crecimiento & desarrollo , Pulmón/anatomía & histología , Mesodermo/metabolismo , Morfogénesis/genética , Transducción de Señal , Tráquea/anatomía & histología , Tráquea/embriología

RESUMEN

The use of fluoroscopic guidance for Maloney dilation is controversial. In order to determine if fluoroscopic analysis would enhance the success of dilation and increase recognition of adverse events, we prospectively studied 125 Maloney dilations in 80 patients (mean age, 69.3 years) with mild esophageal strictures. Most strictures (89%) resulted from acid-peptic disease. Operators included two staff physicians (5 and 25 years of experience) and one trainee (1 year of experience). Dilations were performed with the patient seated upright and the operator noting the presence and amount of resistance (dilator size, 36F to 60F; median, 50F). The fluoroscopic monitor was not visible to the operator, and the results were recorded by an observer who did not communicate with the operator. Operator assessment of Maloney dilation was correct in 122 of 125 procedures. Two failures were interpreted as no passage by the operator when passage had occurred as confirmed by fluoroscopy. One failure was interpreted as passage when no passage had occurred as indicated by fluoroscopy. Adverse events included 1 episode of tracheal intubation and failure to recognize the dilator tip curling in the esophagus as observed by fluoroscopy in 6 of 125 (4.8%) procedures. Operator assessment of resistance was more often associated with curling of the dilator on the greater curve of the stomach than with an esophageal stricture. Greater operator experience tended to correlate with increased success and correct interpretation of dilation. Maloney dilations performed with patients at 30 degrees rather than upright at 90 degrees were associated with a marked increase in unsuccessful dilator passage and curling of dilator tip.(ABSTRACT TRUNCATED AT 250 WORDS)

Asunto(s)

Estenosis Esofágica/terapia , Fluoroscopía , Anciano , Enfermedad Crónica , Dilatación/efectos adversos , Dilatación/métodos , Humanos , Estudios Prospectivos

RESUMEN

A major triticale (X Triticosecale Wittmack) endosperm acid phosphatase (EC 3.1.2.2) (APase) from sib-lines producing plump and shriveled seed was purified 140- and 230-fold to a specific activity of 94 and 153 micromoles per minute per milligram protein respectively, by ammonium sulfate fractionation, ion-exchange chromatography, chromatofocusing, affinity column chromatography, and gel filtration. The purified enzyme from both materials is a monomeric glycoprotein with an apparent molecular weight of 45,700 +/- 500 containing 12% carbohydrate and an apparent isoelectric point of pH 5.9. It hydrolyzes tri- and di-phosphate of nucleosides as well as phosphate esters and exhibits characteristics of ATP-hydrolase and phosphatase. About 2-fold more of the APase was isolated from shriveled seeds, and the purified enzyme exhibited 3- and 5-fold higher V(max) for p-nitrophenyl phosphate and ATP, respectively, than that of plump seed. The I(50) for Pi concentration was 5.5-fold higher in APase of shriveled seed than the plump one. These varied quantitative and kinetic properties substantiate the role of APase in lines with shriveled seeds being reduction of starch accumulation by depleting substrates and energy supply in the cytosol.

RESUMEN

Seed shriveling in the man-made intergeneric hybrid, triticale (x Triticosecale Wittmack) appears to be related to increased activity of endosperm acid phosphatases including para-nitrophenyl phosphatase, ATPase, ADPase, phosphatidic phosphatase, and glucose-1-phosphatase that occur specifically at later stages of seed development. These hydrolases may reduce endogenous substrates for starch synthesis, deplete energy supply for maintenance and biosynthesis of tissue growth, and deassemble membrane structures resulting in a partially filled endosperm and localized necrosis. Electrophoretic isozyme patterns of endosperm acid phosphatase exhibited distinctive differences between lines producing plump and shriveled seeds indicating a divergent role of the isozymes in these two different seed conformations.

RESUMEN

Seven lines of triticale (X Triticosecale Wittmack) with either shriveled or plump seed characteristics were planted in the field, and seed developmental changes in weight, starch content, the activity of starch biosynthetic and degradative enzymes, and ATP content were studied in three consecutive years in Oregon. Experimental results varied among genotypes and with growing environment, but overall indicated that: (a) amylase activity was higher in shriveled lines, but was not directly synchronized with the occurrence of shriveling at later stages of seed formation; (b) ADP-glucose starch synthase contributed to starch accumulation in triticale, but it appeared not to be associated with shriveledness as no stage-related changes were observed; and (c) ADP-glucose pyrophosphorylase activity was 2- to 3-fold higher in plump lines than that of shriveled lines, indicating that this enzyme may play an important role in the degree of plumpness or stach accumulation of triticale seeds.