ABSTRACT
Water shortages in Florida are occurring due to intense utilization of the aquifer system by municipalities and agriculture, and because of continued deficits in annual rainfall. Water districts therefore, are, recommending the use of recycled irrigation water, stormwater runoff, reclaimed municipal sewage water, and lakes for agricultural use. With recycled water, however, there is potential for both introducing and concentrating plant pathogens. In Florida, Erwinia soft-rot bacteria (synonym Pectobacterium) cause extensive crop losses in ornamental plant production. To determine Erwinia spp. population levels, samples were taken monthly for 1 year from four hypereutropic lakes and eight nursery retention ponds. Seventy-seven Erwinia strains were collected by both direct plating and by an enrichment process. With the direct plating method, 0 to 29 CFU/ml were detected on sodium polypectate medium. Significantly higher populations of Erwinia were detected in retention ponds of nurseries that were actively reutilizing their water. Erwinia strains were identified to species by fatty acid analysis and biochemical tests. Strains were further characterized by repetitive element-polymerase chain reaction (rep-PCR) and compared with 120 strains of Erwinia collected from ornamentals over a 17-year period in Florida. Using rep-PCR, most strains were clustered into two heterogeneous populations of E. chrysanthemi and E. carotovora subsp. carotovora in a 1:2 and a 1:4 ratio for isolates from ornamentals and from water, respectively. Within each population of E. chrysanthemi and E. carotovora, genetically different subpopulations could be identified that contained high percentages of Erwinia strains from water sources. Even though genetic differences exist, 99% of the strains from water sources were found to be pathogenic on dieffenbachia. Without water treatment of irrigation and stormwater runoff, there is a potential for both introducing and concentrating Erwinia populations within these water sources.
ABSTRACT
The pituitary hormones prolactin and growth hormone are structurally related. Both hormones exist in the circulation in several molecular forms, differing in aminoacid sequences, posttranslational modifications and fragments produced by proteolytic cleavage. Heterogencity may produce a diversity of inmunological and biological actions. It has been suggested that each of this forms may be a isohormone with a different physiological role. The predominance of one of them in serun could account for the complex and often contradictory actions of the hormones. In addition receptors also have structural homology and so the possibility exist that these hormones share binding affinity to the receptors and can produce endocrinological problems in some special conditions.
Subject(s)
Human Growth Hormone/physiology , Pituitary Hormones/physiology , Prolactin/physiology , Receptors, Pituitary Hormone/physiology , Adult , Female , HumansABSTRACT
This research explored eldercare among Mexican American primary family caregivers from Dallas and Fort Worth, Texas. Although these caregivers expressed feelings of burden, their ethnocultural values of familism placed burden in a broader cultural context in which caregiving was also viewed as an affirmation and fulfillment of core Mexican American cultural values. Mexican American familism includes expressions of family solidarity, ethnocultural determinants of informal caregiving, distrust of culturally alien institutions (particularly nursing homes), and a desire to care for the elderly within the family context regardless of the personal cost or consequences. In contrast to recent research, these findings suggest that it is premature to dismiss familism as a continuing and central influence in the lives of Mexican American family caregivers.
