Witches' Broom Disease of Lime Contributes to Phytoplasma Epidemics and Attracts Insect Vectors.

An insect-transmitted phytoplasma causing Witches' Broom Disease of Lime (WBDL) is responsible for the drastic decline in lime production in several countries. However, it is unclear how WBDL phytoplasma (WBDLp) induces witches' broom symptoms and if these symptoms contribute to the spread of phytoplasma. Here we show that the gene encoding SAP11 of WBDLp (SAP11WBDL) is present in all WBDLp isolates collected from diseased trees. SAP11WBDL interacts with acid lime (Citrus aurantifolia) TCP transcription factors, specifically members of the TB1/CYC class that have a role in suppressing axillary branching in plants. Sampling of WBDLp-infected lime trees revealed that WBDLp titers and SAP11WBDL expression levels were higher in symptomatic leaves compared with asymptomatic sections of the same trees. Moreover, the witches' brooms were found to attract the vector leafhopper. Defense genes that have a role in plant defense responses to bacteria and insects are more downregulated in witches' brooms compared with asymptomatic sections of trees. These findings suggest that witches' broom-affected parts of the trees contribute to WBDL epidemics by supporting higher phytoplasma titers and attracting insect vectors.

Transition in sexual system and sex chromosome evolution in the tadpole shrimp Triops cancriformis.

Transitions in sexual system and reproductive mode may affect the course of sex chromosome evolution, for instance by altering the strength of sexually antagonistic selection. However, there have been few studies of sex chromosomes in systems where such transitions have been documented. The European tadpole shrimp, Triops cancriformis, has undergone a transition from dioecy to androdioecy (a sexual system where hermaphrodites and males coexist), offering an excellent opportunity to test the impact of this transition on the evolution of sex chromosomes. To identify sex-linked markers, to understand mechanisms of sex determination and to investigate differences between sexual systems, we carried out a genome-wide association study using restriction site-associated DNA sequencing (RAD-seq) of 47 males, females and hermaphrodites from one dioecious and one androdioecious population. We analysed 22.9 Gb of paired-end sequences and identified and scored >3000 high coverage novel genomic RAD markers. Presence-absence of markers, single-nucleotide polymorphism association and read depth identified 52 candidate sex-linked markers. We show that sex is genetically determined in T. cancriformis, with a ZW system conserved across dioecious and androdioecious populations and that hermaphrodites have likely evolved from females. We also show that the structure of the sex chromosomes differs strikingly, with a larger sex-linked region in the dioecious population compared with the androdioecious population.

Effects of psychosocial education on adaptation in elderly hemodialysis patients.

The purpose of this experimental field pilot study was to determine whether the application of psychosocial education sessions had an effect on the adaptation level of elderly hemodialysis patients. A pretest, posttest control group design with two randomly selected groups was used. Ten patients, 4 males and 6 females, age 65 years and older, were randomly selected and stratified according to gender, with 2 males and 3 females assigned to either an experimental or a control group. The Psychosocial Adjustment to Illness Scale, Self-Report (PAIS-SR) was administered as a pretest 1 week prior to implementation of the intervention with the experimental group. It was again given as a posttest 30 days after completion of the intervention. The intervention, 7 psychosocial educational sessions with 7 audiotapes and a companion text module, provided information. These sessions were conducted with the experimental group, 2 days a week, during the subjects' hemodialysis treatments, taking approximately 20 minutes each, over a period of 4 1/2 weeks. Data were analyzed utilizing t-tests and descriptive statistics. No significant differences were found between the scores of the pretest and posttest when comparing the two groups. However, a significant value of 0.035 (p < 0.05) was evident in one domain of the PAIS-SR, the domestic environment, when comparing the scores of the pretest and posttest of the experimental group. The application of psychosocial education sessions did not have a significant effect on the adaptation level of elderly hemodialysis patients.

Epoetin alfa--focus on the geriatric patient. Case study of the anemic patient.

According to the Health Care Financing Administration, the largest group receiving dialysis therapy in the United States, constituting 41%, is persons age 65 and older. With 25% of the population expected to be in this age group by the middle of the next century, increasing attention must be paid to this developing "majority patient population." This article addresses the special requirements, major challenges, and management strategies needed to treat older patients with end-stage renal disease.