A Functional Phylogenomic View of the Seed Plants

A novel result of the current research is the development and implementation of a unique functional phylogenomic approach that explores the genomic origins of seed plant diversification. We first use 22,833 sets of orthologs from the nuclear genomes of 101 genera across land plants to reconstruct their phylogenetic relationships. One of the more salient results is the resolution of some enigmatic relationships in seed plant phylogeny, such as the placement of Gnetales as sister to the rest of the gymnosperms. In using this novel phylogenomic approach, we were also able to identify overrepresented functional gene ontology categories in genes that provide positive branch support for major nodes prompting new hypotheses for genes associated with the diversification of angiosperms. For example, RNA interference (RNAi) has played a significant role in the divergence of monocots from other angiosperms, which has experimental support in Arabidopsis and rice. This analysis also implied that the second largest subunit of RNA polymerase IV and V (NRPD2) played a prominent role in the divergence of gymnosperms. This hypothesis is supported by the lack of 24nt siRNA in conifers, the maternal control of small RNA in the seeds of flowering plants, and the emergence of double fertilization in angiosperms. Our approach takes advantage of genomic data to define orthologs, reconstruct relationships, and narrow down candidate genes involved in plant evolution within a phylogenomic view of species' diversification

The incidence, mortality and timing of Pneumocystis jiroveci pneumonia after hematopoietic cell transplantation: a CIBMTR analysis

Pneumocystis jiroveci pneumonia (PJP) is associated with high morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Little is known about PJP infections after HSCT because of the rarity of disease given routine prophylaxis. We report the results of a Center for International Blood and Marrow Transplant Research study evaluating the incidence, timing, prophylaxis agents, risk factors and mortality of PJP after autologous (auto) and allogeneic (allo) HSCT. Between 1995 and 2005, 0.63% allo recipients and 0.28% auto recipients of first HSCT developed PJP. Cases occurred as early as 30 days to beyond a year after allo HSCT. A nested case cohort analysis with supplemental data (n=68 allo cases, n=111 allo controls) revealed that risk factors for PJP infection included lymphopenia and mismatch after HSCT. After allo or auto HSCT, overall survival was significantly poorer among cases vs controls (P=0.0004). After controlling for significant variables, the proportional hazards model revealed that PJP cases were 6.87 times more likely to die vs matched controls (P<0.0001). We conclude PJP infection is rare after HSCT but is associated with high mortality. Factors associated with GVHD and with poor immune reconstitution are among the risk factors for PJP and suggest that protracted prophylaxis for PJP in high-risk HSCT recipients may improve outcomes

Mobile Phone Technology: A New Paradigm for the Prevention, Treatment, and Research of the Non-sheltered “Street” Homeless?

Individuals experiencing homelessness have disproportionately high rates of health problems. Those who perceive themselves as having greater access to their social support networks have better physical and mental health outcomes as well as lower rates of victimization. Mobile phones offer a connection to others without the physical constraints of landlines and, therefore, may make communication (e.g., access to one’s social support networks) more feasible for homeless individuals. This, in turn, could lead toward better health outcomes. This exploratory study examined mobile phone possession and use among a sample of 100 homeless men and women who do not use the shelter system in Philadelphia, PA. Interviews were comprised of the Homeless Supplement to the Diagnostic Interview Schedule, a technology module created for this investigation, and the substance use and psychiatric sections of the Addiction Severity Index. Almost half (44%) of the sample had a mobile phone. In the past 30 days, 100% of those with mobile phones placed or received a call, over half (61%) sent or received a text message, and one fifth (20%) accessed the Internet via their mobile phone. Participants possessed and used mobile phones to increase their sense of safety, responsibility (employment, stable housing, personal business, and sobriety or “clean time”), and social connectedness. Mobile phones could potentially be used by public health/health care providers to disseminate information to the street homeless, to enhance communication between the street homeless and providers, and to increase access for the street homeless to prevention, intervention, and aftercare services. Finally, this technology could also be used by researchers to collect data with this transient population

Multidimensional Social Support and the Health of Homeless Individuals

Homeless individuals often suffer from serious health problems. It has been argued that the homeless are socially isolated, with low levels of social support and social functioning, and that this lack of social resources contributes to their ill health. These observations suggest the need to further explore the relationship between social networks, social support, and health among persons who are homeless. The purpose of this study was to examine the association between multidimensional (cognitive/perceived and behavioral/received) social support and health outcomes, including physical health status, mental health status, and recent victimization, among a representative sample of homeless individuals in Toronto, Canada. Multivariate regression analyses were performed on social support and health outcome data from a subsample of 544 homeless adults, recruited from shelters and meal programs through multistage cluster sampling procedures. Results indicated that participants perceived moderately high levels of access to financial, emotional, and instrumental social support in their social networks. These types of perceived social supports were related to better physical and mental health status and lower likelihood of victimization. These findings highlight a need for more services that encourage the integration of homeless individuals into social networks and the building of specific types of social support within networks, in addition to more research into social support and other social contextual factors (e.g., social capital) and their influence on the health of homeless individuals