123 research outputs found
Comprehensive molecular pharmacology screening reveals potential new receptor interactions for clinically relevant opioids
Most clinically used opioids are thought to induce analgesia through activation of the mu opioid receptor (MOR). However, disparities have been observed between the efficacy of opioids in activating the MOR in vitro and in inducing analgesia in vivo. In addition, some clinically used opioids do not produce cross-tolerance with each other, and desensitization produced in vitro does not match tolerance produced in vivo. These disparities suggest that some opioids could be acting through other targets in vivo, but this has not been comprehensively tested. We thus screened 9 clinically relevant opioids (buprenorphine, hydrocodone, hydromorphone, morphine, 0-desmethyl-tramadol, oxycodone, oxymorphone, tapentadol, tramadol) against 9 pain-related receptor targets (MOR, delta opioid receptor [DOR], kappa opioid receptor [KOR], nociceptin receptor [NOP], cannabinoid receptor type 1 [CB1], sigma-1 receptor [al R], and the monoamine transporters [NET/SERT/DAT]) expressed in cells using radioligand binding and functional activity assays. We found several novel interactions, including monoamine transporter activation by buprenorphine and al R binding by hydrocodone and tapentadol. Tail flick anti-nociception experiments with CD-1 mice demonstrated that the monoamine transporter inhibitor duloxetine selectively promoted buprenorphine anti-nociception while producing no effects by itself or in combination with the most MOR-selective drug oxymorphone, providing evidence that these novel interactions could be relevant in vivo. Our findings provide a comprehensive picture of the receptor interaction profiles of clinically relevant opioids, which has not previously been performed. Our findings also suggest novel receptor interactions for future investigation that could explain some of the disparities observed between opioid performance in vitro and in vivo.Depomed, Inc.; University of ArizonaOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Effects of a beetroot juice with high neobetanin content on the early-phase insulin response in healthy volunteers
Produce rich in phytochemicals may alter postprandial glucose and insulin responses by interacting with the pathways that regulate glucose uptake and insulin secretion in humans. The aims of the present study were to assess the phytochemical constituents of red beetroot juice and to measure the postprandial glucose and insulin responses elicited by either 225 ml beetroot juice (BEET), a control beverage matched for macronutrient content (MCON) or a glucose beverage in healthy adults. Beetroot juice was a particularly rich source of betalain degradation compounds. The orange/yellow pigment neobetanin was measured in particularly high quantities (providing 1·3 g in the 225 ml). A total of sixteen healthy individuals were recruited, and consumed the test meals in a controlled single-blind cross-over design. Results revealed a significant lowering of the postprandial insulin response in the early phase (0–60 min) (P < 0·05) and a significantly lower glucose response in the 0–30 min phase (P < 0·05) in the BEET treatment compared with MCON. Betalains, polyphenols and dietary nitrate found in the beetroot juice may each contribute to the observed differences in the postprandial insulin concentration
A new breakfast cereal containing guar gum reduces postprandial plasma glucose and insulin concentrations in normal-weight human subjects
A Uniqueness Theorem for Constraint Quantization
This work addresses certain ambiguities in the Dirac approach to constrained
systems. Specifically, we investigate the space of so-called ``rigging maps''
associated with Refined Algebraic Quantization, a particular realization of the
Dirac scheme. Our main result is to provide a condition under which the rigging
map is unique, in which case we also show that it is given by group averaging
techniques. Our results comprise all cases where the gauge group is a
finite-dimensional Lie group.Comment: 23 pages, RevTeX, further comments and references added (May 26. '99
Study protocol: a pragmatic randomised controlled trial of a 12-week physical activity and nutritional education program for overweight Aboriginal and Torres Strait Islander women
<p>Abstract</p> <p>Background</p> <p>Aboriginal and Torres Strait Islander women have a higher prevalence and incidence of obesity and type 2 diabetes than non-Indigenous Australian women. Physical inactivity is a key modifiable risk factor for obesity and evidence shows that even modest reductions in waist circumference (WC) have significant health benefits. Trialing physical activity programs in difficult-to-reach high risk groups, especially urban Indigenous Australians poses distinct implementation challenges.</p> <p>Methods/Design</p> <p>The trial objective is to evaluate the effectiveness of a structured 12-week physical activity group program with nutritional advice. The design is a pragmatic randomised controlled trial. This study protocol describes the implementation and evaluation of the program. Participants are randomised into either an intervention or waitlisted group. The waitlisted group have a 12 month waiting period before commencing the 12-week program. Participant data is collected at baseline, 12, 24 and 52 weeks. Participants are Aboriginal and Torres Strait Islander women, aged 18-64 years with a waist circumference greater than 80 centimetres residing in Adelaide. The primary outcome measure is WC change immediately post program from baseline. Secondary outcomes include short term and long term changes in WC, weight, blood pressure, fasting blood glucose, insulin, insulin resistance (calculated HOMA), haemoglobin A1C (HbA1C), triglycerides and C-reactive protein (CRP). Behavioural and psychosocial surveys are administered to assess physical activity, dietary intake and the participant's motivation, self-efficacy and perceived social support for physical activity. Qualitative interviews focusing on participants' motivation, enablers and barriers to healthy eating and physical activity will be undertaken. Implementation fidelity and participation are also assessed.</p> <p>Discussion</p> <p>The Aboriginal and Torres Strait Islander Women's Fitness Program (WFP) is designed to provide a rigorous physiological and client-based evaluation of a structured 12-week program aimed to increase metabolic fitness and reduce WC in this high risk population. Evaluation results aim to provide the support necessary to design programs that are accessible, affordable and effective at reducing WC, while also improving the metabolic profile of overweight Aboriginal and Torres Strait Islander women.</p> <p>Trial registration</p> <p>Australian New Zealand Clinical Trials Registry <a href="http://www.anzctr.org.au/ACTRN12610000224022.aspx">ACTRN12610000224022</a></p
Recomposing consumption: defining necessities for sustainable and equitable well-being
This paper focuses on consumption in the affluent world and the resulting level, composition and distribution of consumption-based emissions. It argues that public policy should foster the recomposition of consumption, while not disadvantaging poorer groups in the population. To combine these two imperatives entails making a distinction between goods and services that are necessary for a basic level of well-being, and those that are surplus to this requirement. The argument proceeds in six stages. First, the paper outlines a theory of universal need, as an alternative conception of well-being to consumer preference satisfaction. Second, it proposes a dual strategy methodology for identifying need satisfiers or necessities in a given social context. Then, it applies this methodology to identify a minimum bundle of necessary consumption items in the UK and speculates how it might be used to identify a maximum bundle for sustainable consumption. The next part looks at corporate barriers and structural obstacles in the path of sustainable consumption. The following part reveals a further problem: mitigation policies can result in perverse distributional outcomes when operating in contexts of great inequality. The final section suggests four ecosocial public policies that would simultaneously advance sustainable and equitable consumption in rich nations
Best practice for motor imagery: a systematic literature review on motor imagery training elements in five different disciplines
<p>Abstract</p> <p>Background</p> <p>The literature suggests a beneficial effect of motor imagery (MI) if combined with physical practice, but detailed descriptions of MI training session (MITS) elements and temporal parameters are lacking. The aim of this review was to identify the characteristics of a successful MITS and compare these for different disciplines, MI session types, task focus, age, gender and MI modification during intervention.</p> <p>Methods</p> <p>An extended systematic literature search using 24 databases was performed for five disciplines: Education, Medicine, Music, Psychology and Sports. References that described an MI intervention that focused on motor skills, performance or strength improvement were included. Information describing 17 MITS elements was extracted based on the PETTLEP (physical, environment, timing, task, learning, emotion, perspective) approach. Seven elements describing the MITS temporal parameters were calculated: study duration, intervention duration, MITS duration, total MITS count, MITS per week, MI trials per MITS and total MI training time.</p> <p>Results</p> <p>Both independent reviewers found 96% congruity, which was tested on a random sample of 20% of all references. After selection, 133 studies reporting 141 MI interventions were included. The locations of the MITS and position of the participants during MI were task-specific. Participants received acoustic detailed MI instructions, which were mostly standardised and live. During MI practice, participants kept their eyes closed. MI training was performed from an internal perspective with a kinaesthetic mode. Changes in MI content, duration and dosage were reported in 31 MI interventions. Familiarisation sessions before the start of the MI intervention were mentioned in 17 reports. MI interventions focused with decreasing relevance on motor-, cognitive- and strength-focused tasks. Average study intervention lasted 34 days, with participants practicing MI on average three times per week for 17 minutes, with 34 MI trials. Average total MI time was 178 minutes including 13 MITS. Reporting rate varied between 25.5% and 95.5%.</p> <p>Conclusions</p> <p>MITS elements of successful interventions were individual, supervised and non-directed sessions, added after physical practice. Successful design characteristics were dominant in the Psychology literature, in interventions focusing on motor and strength-related tasks, in interventions with participants aged 20 to 29 years old, and in MI interventions including participants of both genders. Systematic searching of the MI literature was constrained by the lack of a defined MeSH term.</p
The role of wingbeat frequency and amplitude in flight power
Body-mounted accelerometers provide a new prospect for estimating power use in flying birds, as the signal varies with the two major kinematic determinants of aerodynamic power: wingbeat frequency and amplitude. Yet wingbeat frequency is sometimes used as a proxy for power output in isolation. There is, therefore, a need to understand which kinematic parameter birds vary and whether this is predicted by flight mode (e.g. accelerating, ascending/descending flight), speed or morphology. We investigate this using high-frequency acceleration data from (i) 14 species flying in the wild, (ii) two species flying in controlled conditions in a wind tunnel and (iii) a review of experimental and field studies. While wingbeat frequency and amplitude were positively correlated, R2 values were generally low, supporting the idea that parameters can vary independently. Indeed, birds were more likely to modulate wingbeat amplitude for more energy-demanding flight modes, including climbing and take-off. Nonetheless, the striking variability, even within species and flight types, highlights the complexity of describing the kinematic relationships, which appear sensitive to both the biological and physical context. Notwithstanding this, acceleration metrics that incorporate both kinematic parameters should be more robust proxies for power than wingbeat frequency alone
Advances in structure elucidation of small molecules using mass spectrometry
The structural elucidation of small molecules using mass spectrometry plays an important role in modern life sciences and bioanalytical approaches. This review covers different soft and hard ionization techniques and figures of merit for modern mass spectrometers, such as mass resolving power, mass accuracy, isotopic abundance accuracy, accurate mass multiple-stage MS(n) capability, as well as hybrid mass spectrometric and orthogonal chromatographic approaches. The latter part discusses mass spectral data handling strategies, which includes background and noise subtraction, adduct formation and detection, charge state determination, accurate mass measurements, elemental composition determinations, and complex data-dependent setups with ion maps and ion trees. The importance of mass spectral library search algorithms for tandem mass spectra and multiple-stage MS(n) mass spectra as well as mass spectral tree libraries that combine multiple-stage mass spectra are outlined. The successive chapter discusses mass spectral fragmentation pathways, biotransformation reactions and drug metabolism studies, the mass spectral simulation and generation of in silico mass spectra, expert systems for mass spectral interpretation, and the use of computational chemistry to explain gas-phase phenomena. A single chapter discusses data handling for hyphenated approaches including mass spectral deconvolution for clean mass spectra, cheminformatics approaches and structure retention relationships, and retention index predictions for gas and liquid chromatography. The last section reviews the current state of electronic data sharing of mass spectra and discusses the importance of software development for the advancement of structure elucidation of small molecules
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