Tight coupling of leaf area index to canopy nitrogen and phosphorus across heterogeneous tallgrass prairie communities

Nitrogen (N) and phosphorus (P) are limiting nutrients for many plant communities worldwide. Foliar N and P along with leaf area are among the most important controls on photosynthesis and hence productivity. However, foliar N and P are typically assessed as species level traits, whereas productivity is often measured at the community scale. Here, we compared the community-level traits of leaf area index (LAI) to total foliar nitrogen (TFN) and total foliar phosphorus (TFP) across nearly three orders of magnitude LAI in grazed and ungrazed tallgrass prairie in north-eastern Kansas, USA. LAI was strongly correlated with both TFN and TFP across communities, and also within plant functional types (grass, forb, woody, and sedge) and grazing treatments (bison or cattle, and ungrazed). Across almost the entire range of LAI values and contrasting communities, TFN:TFP ratios indicated co-limitation by N and P in almost all communities; this may further indicate a community scale trend of an optimal N and P allocation per unit leaf area for growth. Previously, results from the arctic showed similar tight relationships between LAI:TFN, suggesting N is supplied to canopies to maximize photosynthesis per unit leaf area. This tight coupling between LAI, N, and P in tallgrass prairie suggests a process of optimal allocation of N and P, wherein LAI remains similarly constrained by N and P despite differences in species composition, grazing, and canopy density

Microarray-based identification and RT-PCR test screening for epithelial-specific mRNAs in peripheral blood of patients with colon cancer

BACKGROUND: The efficacy of screening for colorectal cancer using a simple blood-based assay for the detection of tumor cells disseminated in the circulation at an early stage of the disease is gaining positive feedback from several lines of research. This method seems able to reduce colorectal cancer mortality and may replace colonoscopy as the most effective means of detecting colonic lesions. METHODS: In this work, we present a new microarray-based high-throughput screening method to identifying candidate marker mRNAs for the early detection of epithelial cells diluted in peripheral blood cells. This method includes 1. direct comparison of different samples of colonic mucosa and of blood cells to identify consistent epithelial-specific mRNAs from among 20,000 cDNA assayed by microarray slides; 2. identification of candidate marker mRNAs by data analysis, which allowed selection of only 10 putative differentially expressed genes; 3. Selection of some of the most suitable mRNAs (TMEM69, RANBP3 and PRSS22) that were assayed in blood samples from normal subjects and patients with colon cancer as possible markers for the presence of epithelial cells in the blood, using reverse transcription – polymerase chain reaction (RT-PCR). RESULTS: Our present results seem to provide an indication, for the first time obtained by genome-scale screening, that a suitable and consistent colon epithelium mRNA marker may be difficult to identify. CONCLUSION: The design of new approaches to identify such markers is warranted

Vaccination against Human Influenza A/H3N2 Virus Prevents the Induction of Heterosubtypic Immunity against Lethal Infection with Avian Influenza A/H5N1 Virus

Annual vaccination against seasonal influenza viruses is recommended for certain individuals that have a high risk for complications resulting from infection with these viruses. Recently it was recommended in a number of countries including the USA to vaccinate all healthy children between 6 and 59 months of age as well. However, vaccination of immunologically naïve subjects against seasonal influenza may prevent the induction of heterosubtypic immunity against potentially pandemic strains of an alternative subtype, otherwise induced by infection with the seasonal strains. Here we show in a mouse model that the induction of protective heterosubtypic immunity by infection with a human A/H3N2 influenza virus is prevented by effective vaccination against the A/H3N2 strain. Consequently, vaccinated mice were no longer protected against a lethal infection with an avian A/H5N1 influenza virus. As a result H3N2-vaccinated mice continued to loose body weight after A/H5N1 infection, had 100-fold higher lung virus titers on day 7 post infection and more severe histopathological changes than mice that were not protected by vaccination against A/H3N2 influenza. The lack of protection correlated with reduced virus-specific CD8+ T cell responses after A/H5N1 virus challenge infection. These findings may have implications for the general recommendation to vaccinate all healthy children against seasonal influenza in the light of the current pandemic threat caused by highly pathogenic avian A/H5N1 influenza viruses

Shared decision making and experiences of patients with long-term conditions : has anything changed?

Background Medication problems among patients with long-term conditions (LTCs) are well documented. Measures to support LTC management include: medicine optimisation services by community pharmacists such as the Medicine Use Review (MUR) service in England, implementation of shared decision making (SDM), and the availability of rapid access clinics in primary care. This study aimed to investigate the experience of patients with LTCs about SDM including medication counselling and their awareness of community pharmacy medication review services. Methods A mixed research method with a purposive sampling strategy to recruit patients was used. The quantitative phase involved two surveys, each requiring a sample size of 319. The first was related to SDM experience and the second to medication counselling at discharge. Patients were recruited from medical wards at St. George’s and Croydon University Hospitals.The qualitative phase involved semi-structured interviews with 18 respiratory patients attending a community rapid access clinic. Interviews were audio-recorded and transcribed verbatim. Thematic analysis using inductive/deductive approaches was employed. Survey results were analysed using descriptive statistics. Results The response rate for surveys 1 and 2 survey was 79% (n = 357/450) and 68.5% (240/350) respectively. Survey 1 showed that although 70% of patients had changes made to their medications, only 40% were consulted about them and two-thirds (62.2%) wanted to be involved in SDM. In survey 2, 37.5% of patients thought that medication counselling could be improved. Most patients (88.8%) were interested in receiving the MUR service; however 83% were not aware of it. The majority (57.9%) were interested in receiving their discharge medications from community pharmacies. The interviews generated three themes; lack of patient-centered care and SDM, minimal medication counselling provided and lack of awareness about the MUR service. Conclusion Although patients wanted to take part in SDM, yet SDM and medication counselling are not optimally provided. Patients were interested in the MUR service; however there was lack of awareness and referral for this service. The results propose community pharmacy as a new care pathway for medication supply and counselling post discharge. This promotes a change of health policy whereby community-based services are used to enhance the performance of acute hospitals