P metabolism and transport in AM fungi

The arbuscular mycorrhizal symbiosis is mutualistic, based on reciprocal transfer of P from the fungus to the plant and carbon from the plant to the fungus. Thus P is a most important 'currency' in the symbiosis. After absorbing P from the soil solution, the fungi first incorporate it into the cytosolic pool, and the excess P is transferred to the vacuoles. The vacuolar P pool probably plays a central role in P supply to the plant. The main forms of inorganic P in fungal vacuoles are orthophosphate and polyphosphate, but organic P molecules may also be present. Long distance translocation of P from the site of uptake in the external mycelium to the site of transfer to the plant is probably achieved via transfer of vacuolar components. This transport would be mediated either by protoplasmic streaming or the motile tubular vacuole-like system. The site of release of P into the interfacial apoplast and thence to the plant is most probably the fungal arbuscules. The biochemical and biophysical processes involved in P metabolism and transfer between cellular compartments in the symbiosis are currently not well understood. Some recent investigations of substrate specificities of phosphatase-type enzymes in AM fungi and other eukaryotic microorganisms, however, have shed new light on earlier results and permit the construction of a hypothetical scheme of P-flow, including possible regulatory factors. Steps in this scheme are experimentally testable and should stimulate future researc

Unraveling the Influence of Arbuscular Mycorrhizal Colonization on Arsenic Tolerance in Medicago: Glomus mosseae is More Effective than G. intraradices, Associated with Lower Expression of Root Epidermal Pi Transporter Genes

We used medic (Medicago truncatula) to investigate effects of inoculation with two arbuscular mycorrhizal (AM) fungi and application of arsenate (AsV) and phosphate (Pi) on mechanisms underlying increased tolerance (in terms of growth) of AM plants to AsV. We tested the hypotheses that (1) inoculation with AM fungi results in down-regulation of MtPht1;1 and MtPht1;2 genes (encoding high-affinity Pi and AsV uptake systems in the direct root epidermal pathway) and up-regulation of the AM-induced MtPht1;4 (responsible for transfer of Pi from the arbuscular interface to cortical cells), and (2) these changes are involved in decreased As uptake relative to P uptake and hence increased As tolerance. We also measured expression of MtMT4, a Pi starvation-inducible gene, other genes encoding Pi uptake systems (MtPht 1;5 and MtPht1;6) and arsenate reductase (MtACR) and phytochelatin synthase (MtPCS), to gain insights into broader aspects of P transfers in AM plants and possible detoxification mechanisms. Medic responded slightly to AM colonization in terms of growth in the absence of As, but positively in terms of P uptake. Both growth and P responses in AM plants were positive when As was applied, indicating As tolerance relative to non-mycorrhizal (NM) plants. All AM plants showed high expression of MtPT4 and those inoculated with Glomus mosseae showed higher selectivity against As (shown by P/As molar ratios) and much lower expression of MtPht1;1 (and to some extent MtPht1;2) than Glomus intraradices-inoculated or NM plants. Results are consistent with increased P/As selectivity in AM plants (particularly those inoculated with G. mosseae) as a consequence of high P uptake but little or no As uptake via the AM pathway. However, the extent to which selectivity is dependent on down-regulation of direct Pi and AsV uptake through epidermal cells is still not clear. Marked up-regulation of a PCS gene and an ACR gene in AM plants may also be involved and requires further investigation

Nurses Alumni Association Bulletin, Fall 2000

2000 - 2001 Meeting Date Calendar 2001 Annual Luncheon & Meeting Notice 2000 Fall Social Officers and Committee Chairs Bulletin Publication Committee The President\u27s Message Treasurer\u27s Report Resume of Minutes Alumni Office News Committee Reports Nurses Relief Trust Fund Clara Melville - Adele Lewis Scholarship Fund Satellite Report - Harrisburg Satellite The Fall Luncheon Nominating Alumni Bulletin Development News about our Graduates Presentation on Leadership -Tribute to Janet C. Hindson Thank You Patient Assimilators Third Janet C. Hindson Award Janet C. Hindson Award Qualifications Pinning Ceremony Jeff HOPE Keepsakes Memoirs Happy Birthday 50th Anniversary Class Luncheon Photos Kodak Moment In Memoriam, Names of Deceased Graduates Class News Scholarship Fund Application Certification Reimbursement Application Relief Fund Application Pins, Transcripts, Class Address List, Change of Address Forms Notes Campus Map List of Hotel

Nurses Alumni Association Bulletin, Fall 2001

2001 - 2002 Meeting Date Calendar 2002 Annual Luncheon & Meeting Notice Bulletin Publication Committee, Officers and Committee Chairs The President\u27s Message Treasurer\u27s Financial Report Auditor\u27s Financial Report Alumni Scholarship Fund Resume of Minutes Alumni Office News Committee Reports Nurses Relief Trust Fund Clara Melville - Adele Lewis Scholarship Fund Nominating Social -Annual May Luncheon Social - Fall Luncheon of 2000 Central PA Satellite Committee Report Bulletin Development Annual Giving Contributors News About Our Graduates Janet C. Hindson Award Janet C. Hindson Award - Qualifications Army Nurse Corps Nursing 101 A Loving Aunt\u27s Thoughts Volunteers In Medicine Happy Birthday - To Be 80 Or More Luncheon Photos Collage Fiftieth Anniversary - Class of 1951 In Memoriam, Names of Deceased Graduates Class News Application for Nurses Scholarship Fund Application for Certification Application for Relief Fund Benefits Miscellaneous: Pins, Transcripts, Class Address List, Change of Address Forms Campus Map List of Hotels Note

Special Education in Juvenile Residential Facilities: Can Animals Help?

Children with emotional/behavioral disorders (EBD) are arguably one of the highest at-risk groups for dropping out before graduating high school. They are the group of students with disabilities who are most likely to be educated in residential facilities. Residential facilities such as Green Chimneys have incorporated animals into the treatment milieu with success. Animals have been used in various settings to improve the quality of life as well as the emotional and physical needs of people served by these facilities. This article describes the requirements for using animals in residential treatment, the limitations of such programs, and the research findings for the use of animal-assisted therapy or activities (AAT/AAA). Using Gardner’s (1999) iteration of his theory of multiple intelligence, the authors proposed an understanding of how these treatments might be improve the intelligence of a child with EBD. Requirements for effective treatment of special needs children were discussed

What is the significance of the arbuscular mycorrhizal colonisation of many economically important crop plants?

Abstract Arbuscular mycorrhizal (AM) symbioses are widespread in land plants but the extent to which they are functionally important in agriculture remains unclear, despite much previous research. We ask focused questions designed to give new perspectives on AM function, some based on recent research that is overturning past beliefs. We address factors that determine growth responses (from positive to negative) in AM plants, the extent to which AM plants that lack positive responses benefit in terms of nutrient (particularly phosphate: P) uptake, whether or not AM and nonmycorrhizal (NM) plants acquire different forms of soil P, and the cause(s) of AM 'growth depressions'. We consider the relevance of laboratory work to the agricultural context, including effects of high (available) soil P on AM fungal colonisation and whether AM colonisation may be deleterious to crop production due to fungal 'parasitism'. We emphasise the imperative for research that is aimed at increasing benefits of AM symbioses in the field at a time of increasing prices of P-fertiliser, and increasing demands on agriculture to feed the world. In other words, AM symbioses have key roles in providing ecosystem services that are receiving increasing attention worldwide

The influence of facility and home pen design on the welfare of the laboratory-housed dog

We have an ethical and scientific obligation to Refine all aspects of the life of the laboratory-housed dog. Across industry there are many differences amongst facilities, home pen design and husbandry, as well as differences in features of the dogs such as strain, sex and scientific protocols. Understanding how these influence welfare, and hence scientific output is therefore critical. A significant proportion of dogs’ lives are spent in the home pen and as such, the design can have a considerable impact on welfare. Although best practice guidelines exist, there is a paucity of empirical evidence to support the recommended Refinements and uptake varies across industry. In this study, we examine the effect of modern and traditional home pen design, overall facility design, husbandry, history of regulated procedures, strain and sex on welfare-indicating behaviours and mechanical pressure threshold. Six groups of dogs from two facilities (total n=46) were observed in the home pen and tested for mechanical pressure threshold. Dogs which were housed in a purpose-built modern facility or in a modern design home pen showed the fewest behavioural indicators of negative welfare (such as alert or pacing behaviours) and more indicators of positive welfare (such as resting) compared to those in a traditional home pen design or traditional facility. Welfare indicating behaviours did not vary consistently with strain, but male dogs showed more negative welfare indicating behaviours and had greater variation in these behaviours than females. Our findings showed more positive welfare indicating behaviours in dogs with higher mechanical pressure thresholds. We conclude that factors relating to the design of home pens and implementation of Refinements at the facility level have a significant positive impact on the welfare of laboratory-housed dogs, with a potential concomitant impact on scientific endpoints

Characteristics of gentamicin uptake in the isolated crista ampullaris of the inner EAR of the guinea pig

The characteristics of aminoglycoside uptake in the inner ear were investigated in the isolated crista ampullaris. The organ was incubated with radiolabeled gentamicin, and the stable, nonexchangeable radioactivity was considered the intracellular pool of the drug. Gentamicin was transported against a concentration gradient, and the resulting tissue to medium ratios ranged from 1.4 to 18.6. Transport was inhibited by reduction in temperature or by the addition of metabolic blockers, indicative of an energy-dependent component. The uptake system showed at least two sites, the first a high-affinity site with a dissociation constant and a capacity of n = 0.2 pmole/crista; the second had a and a capacity of n = 11 pmoles/crista. Aminoglycosides competed with uptake of gentamicin in the order netilmicin >= neomycin > tobramycin, and polyamines competed in the order spermine > spermidine > putrescine; glucosamine and the basic amino acids lysine and asparagine were ineffective, excluding the participation of glucose and basic amino acid transport systems in gentamicin uptake. These results along with direct comparisons with some characteristics of putrescine uptake suggest that aminoglycoside and polyamine transport have common features in the crista ampullaris.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26879/1/0000445.pd

Wee1-Regulated Apoptosis Mediated by the Crk Adaptor Protein in Xenopus Egg Extracts

Many of the biochemical reactions of apoptotic cell death, including mitochondrial cytochrome c release and caspase activation, can be reconstituted in cell-free extracts derived from Xenopus eggs. In addition, because caspase activation does not occur until the egg extract has been incubated for several hours on the bench, upstream signaling processes occurring before full apoptosis are rendered accessible to biochemical manipulation. We reported previously that the adaptor protein Crk is required for apoptotic signaling in egg extracts (Evans, E.K., W. Lu, S.L. Strum, B.J. Mayer, and S. Kornbluth. 1997. EMBO (Eur. Mol. Biol. Organ.) J. 16:230–241). Moreover, we demonstrated that removal of Crk Src homology (SH)2 or SH3 interactors from the extracts prevented apoptosis. We now report the finding that the relevant Crk SH2-interacting protein, important for apoptotic signaling in the extract, is the well-known cell cycle regulator, Wee1. We have demonstrated a specific interaction between tyrosine-phosphorylated Wee1 and the Crk SH2 domain and have shown that recombinant Wee1 can restore apoptosis to an extract depleted of SH2 interactors. Moreover, exogenous Wee1 accelerated apoptosis in egg extracts, and this acceleration was largely dependent on the presence of endogenous Crk protein. As other Cdk inhibitors, such as roscovitine and Myt1, did not act like Wee1 to accelerate apoptosis, we propose that Wee1–Crk complexes signal in a novel apoptotic pathway, which may be unrelated to Wee1's role as a cell cycle regulator

Attitudes and Opinions About Direct-to-Consumer Genetic Testing in Undergraduate Science Students

Background: There has been exponential growth in the number of direct-to-consumer genetic testing kits sold in the past decade. Consumers utilize direct-to-consumer genetic tests for a number of reasons which include learning about one’s ancestry and potential ways to manage health. Emerging adults tend to be early adopters of new technologies; however, there has been little research regarding the opinions about direct-to-consumer genetic testing in emerging adults. Methods: Data came from a study conducted in an upper-level biology course focusing on understanding undergraduate science students’ overall experiences with receiving personalized genetic testing results from 23andMe. The present study used data collected at the baseline assessment which assessed their opinions and attitudes about direct-to-consumer genetic testing (N=133). Results: Over 80% of participants would recommend direct-to-consumer genetic testing options including carrier status reports, DNA ancestry reports, wellness reports, and trait reports to others. However, participants were not as confident that others would be able to accurately interpret their test results. Additionally, more than two-thirds of the participants stated that they would ask a healthcare provider to help interpret their personalized genetic test results. Conclusions: Participants lack confidence in both their ability to interpret their own results and others to interpret their results. It is important for direct-to-consumer genetic testing companies to educate consumers before providing results in order to minimize potential harms due to misinterpretation of results. Further research is needed to assess motivations to participate in direct-to-consumer genetic testing, impact of testing, and understanding of genetic testing results in emerging adults.https://scholarscompass.vcu.edu/gradposters/1124/thumbnail.jp