Families, Metaphysical Dreams, and Villages

Neither Sen. Dole nor President Clinton were speaking of either families or villages

Delineation of ligand binding and receptor signaling activities of purified P2Y receptors reconstituted with heterotrimeric G proteins

P2Y receptors are G protein coupled receptors that respond to extracellular nucleotides to promote a multitude of signaling events. Our laboratory has purified several P2Y receptors with the goal of providing molecular insight into their: (1) ligand binding properties, (2) G protein signaling selectivities, and (3) regulation by RGS proteins and other signaling cohorts. The human P2Y1 receptor and the human P2Y12 receptor, both of which are intimately involved in ADP-mediated platelet aggregation, were purified to near homogeneity and studied in detail. After high-level expression from recombinant baculovirus infection of Sf9 insect cells, approximately 50% of the receptors were successfully extracted with digitonin. Purification of nearly homogeneous epitope-tagged P2Y receptor was achieved using metal-affinity chromatography followed by other traditional chromatographic steps. Yields of purified P2Y receptors range from 10 to 100 μg/l of infected cells. Once purified, the receptors were reconstituted in model lipid vesicles along with their cognate G proteins to assess receptor function. Agonist-promoted increases in steady-state GTPase assays demonstrated the functional activity of the reconstituted purified receptor. We have utilized this reconstitution system to assess the action of various nucleotide agonists and antagonists, the relative G protein selectivity, and the influence of other proteins, such as phospholipase C, on P2Y receptor-promoted signaling. Furthermore, we have identified the RGS expression profile of platelets and have begun to assess the action of these RGS proteins in a reconstituted P2Y receptor/G protein platelet model

A phase II study of capecitabine and oxalplatin combination chemotherapy in patients with inoperable adenocarcinoma of the gall bladder or biliary tract

Background: Advanced biliary tract carcinomas are associated with a poor prognosis, and palliative chemotherapy has only modest benefit. This multi-centre phase II study was conducted to determine the efficacy of capecitabine in combination with oxaliplatin in patients with inoperable gall bladder or biliary tract cancer. Methods: This was a Phase II, non-randomised, two-stage Simon design, multi-centre study. Ethics approval was sought and obtained by the North West MREC, and then locally by the West Glasgow Hospitals Research Ethics Com mittee. Eligible patients with inoperable locally advanced or metastatic adenocarcinoma of the gall bladder or biliary tract and with adequate performance status, haematologic, renal, and hepatic function were treated with capecit abine (1000 mg/m2 po, twice daily, days 1–14) and oxaliplatin (130 mg/m2 i.v., day 1) every 3 weeks for up to six cycles. The primary objective of the study was to determine the objective tumour response rates (complete and partial). The secondary objectives included assessment of toxicity, progression-free survival, and overall survival. Results: Forty-three patients were recruited between July 2003 and December 2005. The regimen was well tolerated with no grade 3/4 neutropenia or thrombocytopenia. Grade 3/4 sensory neuropathy was observed in six patients. Two-thirds of patients received their chemotherapy without any dose delays. Overall response rate was 23.8 % (95 % CI 12.05–39.5 %). Stable disease was observed in a further 13 patients (31 %) and progressive disease observed in 12 (28.6 %) of patients. The median progression-free survival was 4.6 months (95 % CI 2.8–6.4 months; Fig. 1) and the median overall survival 7.9 months (95 % CI 5.3–10.4 months; Fig. 2). Conclusion: Capecitabine combined with oxaliplatin has a lower disease control and shorter overall survival than the combination of cisplatin with gemcitabine which has subsequently become the standard of care in this disease. How ever, capecitabine in combination with oxaliplatin does have modest activity in this disease, and can be considered as an alternative treatment option for patients in whom cisplatin and/or gemcitabine are contra-indicated

What Does It Take: The Roles, Responsibilities, and Fidelity to Implement a Physical Activity in Public HealthTraining

Cooperative Extension Service (Extension) Agents are tasked with incorporating physical activity promotion in their work. Physical activity training interventions rarely report specific structures (dose, content) and measures (fidelity, resource cost). The study’s purpose was to evaluate the feasibility and resource costs of Physical Activity in Cooperative Extension (PACE), a training to increase physical activity in public health competency. PACE is a virtual, 9-week, 18-hour general capacity-building training based on the Interactive Systems Framework. Fidelity was calculated as the proportion of objectives delivered as intended and total time to deliver core components. Resource cost was calculated as the time spent on each implementation strategy and responsibility and total time spent delivering PACE. Fidelity was 93% (39/42 planned objectives delivered as intended). PACE required 183 hours to implement, with session delivery (45 hours) and participant communication (40 hours) requiring the most time. Overall, time spent included 37 hours per delivery team member and 18 hours per PACE participant. The personnel time spent was within the standard time spent on other Extension training protocols and perceived as feasible. Fidelity to session components was high and easy to track. Future work should determine the scalability and sustainability of PACE within Extension nationally

Student evaluation of an OSCE in paediatrics at the University of the West Indies, Jamaica

BACKGROUND: The Faculty of Medical Sciences, University of the West Indies first implemented the Objective Structured Clinical Examination (OSCE) in the final MB Examination in Medicine and Therapeutics during the 2000–2001 academic year. Simultaneously, the Child Health Department initiated faculty and student training, and instituted the OSCE as an assessment instrument during the Child Health (Paediatric) clerkship in year 5. The study set out to explore student acceptance of the OSCE as part of an evaluation of the Child Health clerkship. METHODS: A self-administered questionnaire was completed by successive groups of students immediately after the OSCE at the end of each clerkship rotation. Main outcome measures were student perception of examination attributes, which included the quality of instructions and organisation, the quality of performance, authenticity and transparency of the process, and usefulness of the OSCE as an assessment instrument compared to other formats. RESULTS: There was overwhelming acceptance of the OSCE in Child Health with respect to the comprehensiveness (90%), transparency (87%), fairness (70%) and authenticity of the required tasks (58–78%). However, students felt that it was a strong anxiety-producing experience. And concerns were expressed regarding the ambiguity of some questions and inadequacy of time for expected tasks. CONCLUSION: Student feedback was invaluable in influencing faculty teaching, curriculum direction and appreciation of student opinion. Further psychometric evaluation will strengthen the development of the OSCE

Design analysis of levitation facility for space processing applications

Containerless processing facilities for the space laboratory and space shuttle are defined. Materials process examples representative of the most severe requirements for the facility in terms of electrical power, radio frequency equipment, and the use of an auxiliary electron beam heater were used to discuss matters having the greatest effect upon the space shuttle pallet payload interfaces and envelopes. Improved weight, volume, and efficiency estimates for the RF generating equipment were derived. Results are particularly significant because of the reduced requirements for heat rejection from electrical equipment, one of the principal envelope problems for shuttle pallet payloads. It is shown that although experiments on containerless melting of high temperature refractory materials make it desirable to consider the highest peak powers which can be made available on the pallet, total energy requirements are kept relatively low by the very fast processing times typical of containerless experiments and allows consideration of heat rejection capabilities lower than peak power demand if energy storage in system heat capacitances is considered. Batteries are considered to avoid a requirement for fuel cells capable of furnishing this brief peak power demand

Human P2Y 14 Receptor Agonists: Truncation of the Hexose Moiety of Uridine-5′-Diphosphoglucose and Its Replacement with Alkyl and Aryl Groups

Uridine-5′-diphosphoglucose (UDPG) activates the P2Y14 receptor, a neuroimmune system GPCR. P2Y14 receptor tolerates glucose substitution with small alkyl or aryl groups or its truncation to uridine-5′-diphosphate (UDP), a full agonist human P2Y14 receptor expressed in HEK-293 cells. 2-Thiouracil derivatives displayed selectivity for activation of the human P2Y14 vs. the P2Y6 receptor, such as 2-thio-UDP 4 (EC50 1.92 nM at P2Y14, 224-fold selectivity vs. P2Y6) and its β-propyloxy ester 18. EC50 of β-methyl ester of UDP and its 2-thio analogue were 2730 and 56 nM, respectively. β-t-Butyl ester of 4 was 11-fold more potent than UDPG, but β-aryloxy or larger, branched β-alkyl esters, such as cyclohexyl, were less potent. Ribose replacement of UDP with a rigid North or South methanocarba (bicyclo[3.1.0]hexane) group abolished P2Y14 receptor agonist activity. α,β-Methylene and difluoromethylene groups were well tolerated at the P2Y14 receptor and are expected to provide enhanced stability in biological systems. α,β-Methylene-2-thio-UDP 11 (EC50 0.92 nM) was 2160-fold selective versus P2Y6. Thus, these nucleotides and their congeners may serve as important pharmacological probes for the detection and characterization of the P2Y14 receptor

Move More, Sit Less: Applying the Physical Activity Guidelines for Americans to Extension Programs

Extension enhances the lives of Americans by translating research-based information related to existing needs into programming that is practical and accessible to the general public. Evidence clearly indicates that physical activity is correlated to positive health outcomes, but despite this conclusion, the majority of Americans do not meet the recommendations for physical activity. The 2nd Edition of the Physical Activity Guidelines for Americans provides guidance for Extension professionals to implement physical activity interventions. We recommend training and technical assistance strategies based on the Interactive Systems Framework to integrate physical activity promotion into all Extension areas

Kinetics and activation of phospholipase C by P2Y purinergic agonists and guanine nucleotides

Membranes prepared from [3H]inositol-labeled turkey erythrocytes express a phospholipase C that is markedly stimulated by stable analogs of GTP (Harden, T. K., Stephens, L., Hawkins, P. T., and Downes, C. P. (1987) J. Biol. Chem. 262, 9057-9061). We now report that P2-purinergic receptor-mediated regulation of the enzyme occurs in the membrane preparation. The order of potency of a series of ATP and ADP analogs for stimulation of inositol phosphate formation, i.e. 2-methylthioadenosine 5'-triphosphate (2MeSATP) greater than adenosine 5'-O-(2-thiodiphosphate) greater than adenosine 5'-O-(3-thiotriphosphate) greater than ATP greater than 5'-adenylyl imidodiphosphate approximately ADP greater than alpha, beta-methyleneadenosine 5'-triphosphate greater than beta, gamma-methyleneadenosine 5'-triphosphate, was consistent with that for the P2Y-purinergic receptor subtype. Agonist-stimulated effects were completely dependent on the presence of guanine nucleotide. Activation of phospholipase C by guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) occurred with a considerable time lag. The rate of activation followed first order kinetics and was markedly increased by increasing concentrations of a P2Y receptor agonist; in contrast, the rate of activation at a fixed agonist concentration was independent of guanine nucleotide concentration. Addition of guanosine 5'-O-(2-thiodiphosphate) (GDP beta S) prior to addition of agonist and GTP, 5'-guanylyl imidodiphosphate (Gpp(NH)p), or GTP gamma S blocked in a concentration-dependent manner the stimulatory effect of guanine nucleotide. GDP beta S, added subsequent to preactivation of membranes with 2MeSATP and GTP gamma S or Gpp(NH)p had only small inhibitory effects on the rate of inositol phosphate production observed over the subsequent 10 min. In contrast, addition of GDP beta S to GTP-preactivated membranes resulted in a rapid return of enzyme activity to the basal state within 60 s. Taken together, the data are consistent with the idea that P2Y receptor activation increases the rate of exchange of GTP and GTP analogs for GDP on the relevant guanine nucleotide regulatory protein. Once the active enzymic species is formed, hydrolysis of guanine nucleotide reverts the enzyme to the inactive state