Absorbed radiation dosimetry of the D3-specific PET radioligand [18F]FluorTriopride estimated using rodent and nonhuman primate

[(18)F]FluorTriopride ([(18)F]FTP) is a dopamine D(3)-receptor preferring radioligand with potential for investigation of neuropsychiatric disorders including Parkinson disease, dystonia and schizophrenia. Here we estimate human radiation dosimetry for [(18)F]FTP based on the ex-vivo biodistribution in rodents and in vivo distribution in nonhuman primates. Biodistribution data were generated using male and female Sprague-Dawley rats injected with ~370 KBq of [(18)F]FTP and euthanized at 5, 30, 60, 120, and 240 min. Organs of interest were dissected, weighed and assayed for radioactivity content. PET imaging studies were performed in two male and one female macaque fascicularis administered 143-190 MBq of [(18)F]FTP and scanned whole-body in sequential sections. Organ residence times were calculated based on organ time activity curves (TAC) created from regions of Interest. OLINDA/EXM 1.1 was used to estimate human radiation dosimetry based on scaled organ residence times. In the rodent, the highest absorbed radiation dose was the upper large intestines (0.32-0.49 mGy/MBq), with an effective dose of 0.07 mSv/MBq in males and 0.1 mSv/MBq in females. For the nonhuman primate, however, the gallbladder wall was the critical organ (1.81 mGy/MBq), and the effective dose was 0.02 mSv/MBq. The species discrepancy in dosimetry estimates for [(18)F]FTP based on rat and primate data can be attributed to the slower transit of tracer through the hepatobiliary track of the primate compared to the rat, which lacks a gallbladder. Out findings demonstrate that the nonhuman primate model is more appropriate model for estimating human absorbed radiation dosimetry when hepatobiliary excretion plays a major role in radiotracer elimination

A total environment of change: exploring social-ecological shifts in subsistence fisheries in Noatak and Selawik, Alaska

Thesis (M.S.) University of Alaska Fairbanks, 2012Arctic ecosystems are undergoing rapid changes as a result of global climate change, with significant implications for the livelihoods of arctic peoples. In this thesis, I use ethnographic research methods to detail prominent environmental changes observed and experienced over the past few decades and to document the impact of these changes on subsistence fishing practices in the Inupiaq communities of Noatak and Selawik in northwestern Alaska. Using in-depth key informant interviews, participant observation, and cultural consensus analysis, I explore local knowledge and perceptions of climate change and other pronounced changes facing the communities of Noatak and Selawik. I find consistent agreement about a range of perceived environmental changes affecting subsistence fisheries in this region, including lower river water levels, decreasing abundances of particular fish species, increasingly unpredictable weather conditions, and increasing presence of beaver, which affect local waterways and fisheries. These observations of environmental changes are not perceived as isolated phenomena, but are experienced in the context of accompanying social changes that are continually reshaping rural Alaska communities and subsistence economies. Consequently, in order to properly assess and understand the impacts of climate change on the subsistence practices in arctic communities, we must also consider the total environment of change that is dramatically shaping the relationship between people, communities, and their surrounding environments.U.S. Fish and Wildlife Service, Office of Subsistence Management, Project Number 10-152, Research Work Order number G10AC00473 from the U.S. Geological Survey, Alaska Cooperative Fish and Wildlife Research Unit, U.S. National Park Service, George Wright Melendenz Climate Change Fellowship, Alaska NSF EPSCoR ProgramIntroduction : arctic climate change and research approach -- Research methods and data analysis -- Noatak and Selawik : patterns of change and continuity -- Observations of climate change and impacts on subsistence fishing -- Climate change in the context of a total environment of change -- Assessing agreement about observations and perceptions of climate change -- Synthesis and future directions -- References -- Appendix

Spatial reorganization of putaminal dopamine D2-like receptors in cranial and hand dystonia

The putamen has a somatotopic organization of neurons identified by correspondence of firing rates with selected body part movements, as well as by complex, but organized, differential cortical projections onto putamen. In isolated focal dystonia, whole putaminal binding of dopamine D(2)-like receptor radioligands is quantitatively decreased, but it has not been known whether selected parts of the putamen are differentially affected depending upon the body part affected by dystonia. The radioligand [(18)F]spiperone binds predominantly to D(2)-like receptors in striatum. We hypothesized that the spatial location of [(18)F]spiperone binding within the putamen would differ in patients with dystonia limited to the hand versus the face, and we tested that hypothesis using positron emission tomography and magnetic resonance imaging. To address statistical and methodological concerns, we chose a straightforward but robust image analysis method. An automated algorithm located the peak location of [(18)F]spiperone binding within the striatum, relative to a brain atlas, in each of 14 patients with cranial dystonia and 8 patients with hand dystonia. The mean (left and right) |x|, y, and z coordinates of peak striatal binding for each patient were compared between groups by t test. The location of peak [(18)F]spiperone binding within the putamen differed significantly between groups (cranial dystonia z<hand dystonia z, p = 0.016). We conclude that in isolated focal dystonia, dopamine D(2)-like receptors are distributed differently in the putamen depending on the body part manifesting dystonia

Synthesis of [ 18 F]fluoroethoxy‐benzovesamicol, a radiotracer for cholinergic neurons

Full experimental details are given for the preparation of [ 18 F]fluoroethoxy‐benzovesamicol, (−)‐( 2R, 3R )‐ trans ‐2‐hydroxy‐3‐(4‐phenylpiperidino)‐5‐(2‐[ 18 F]fluoroethoxy)‐1,2,3,4‐tetralin, a new fluorine‐18 labeled cholinergic neuron mapping agent for use in positron emission tomography (PET). This radiotracer was made by nucleophilic radiofluorination of tosyloxyethoxy‐benzovesamicol, followed by reverse phase HPLC purification, in decay corrected radiochemical yield exceeding 60%.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90363/1/2580330704_ftp.pd

Launch Hardened Cup-Cone Docking Mechanism for Small-Sats

A dual-use docking mechanism that can provide soft dynamic coupling in space and a rigid connection for launch would provide significant benefit to launch cost and weight savings. PSI has developed the Toothed Cup-cone Launch-hardened Androgynous Docking (T-CLAD) mechanism as a solution. The T-CLAD mechanism in an androgynous docking mechanism capable of withstanding launch loads while simultaneously providing self-alignment docking capabilities for on-orbit servicing and refueling. The mechanism is nominally designed for half-ESPA-class satellites but can be sized up and down to different class satellites while keeping full capabilities. The system incorporates an alternating, toothed cup-cone interface and SepNuts to launch harden the system. Furthermore, this cup-cone interface provides a self-alignment system to improve engagement of on-orbit docking. With additional hard-dock latching systems, fuel ports, and electrical ports, the T-CLAD mechanism enables on-orbit servicing within the confines of a launch restraint system. The research covered in this paper presents the design work, concept of operations, mechanism capabilities, and initial testing of the T-CLAD mechanism. An overview of the concept of operations and the versatility of the mechanism for thruster and robotic arm driven docking will be discussed. Furthermore, the ISAM-related missions that the T-CLAD mechanism can be used for will be covered as related to future research and missions. The unique cup-cone interfaces were designed based on expected launch loads and the dynamics of on-orbit slewing and fuel transfer. An experimental prototype was designed and fabricated to validate the initial design work, and the experimental results will be presented along with future plans for development, testing, and integration into an operational system

Highlighting the versatility of the Tracerlab synthesis modules. Part 2: fully automated production of [ 11 C]‐labeled radiopharmaceuticals using a Tracerlab FX C‐Pro

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/89445/1/jlcr1937.pd

Exploratory Survey on European Consumer and Stakeholder Attitudes towards Alternatives for Surgical Castration of Piglets

Simple SummaryIn many countries, surgical castration of piglets without pain relief or anaesthesia is still common practice. Castration is performed to minimise the incidence of boar taint, a bad taste (urine/fecal like), typically present in the meat of 5 to 10% of uncastrated male pigs. It also helps to avoid aggressive and sexual behaviour. For animal welfare reasons, alternatives are being considered, and in some countries, an alternative is already practiced. One option is to perform surgical castration with anaesthesia and relieve pain. A second option is to produce male pigs without castration, which requires detection of tainted carcasses in the slaughter house. A third option is to apply immunocastration: by a two-fold injection of a vaccine, the testes function is inhibited, which reduces boar-like behaviour and avoids boar taint. In this study, we evaluated the acceptability of each of these methods in 16 countries in Europe. Of the 4 presented options, the practice of surgical castration was least accepted (32%), whilst there was a high acceptance of castration with anaesthesia (85%), followed by immunocastration (71%) and production of boars (49%). The developed questionnaire and infographic can be used in future studies to further gain insights in consumer and stakeholder attitudes on this topic.Surgical castration of piglets without pain relief is still common practice in many countries. Possible alternatives for surgical castration are application of pain relief or anaesthesia or production of boars (entire males) and immunocastrates. Each of these alternatives faces advantages and disadvantages which may result in different citizen attitudes and consumers acceptability. Understanding which practice is acceptable to whom and why may further stimulate implementation. Consumer (n = 3251) and stakeholder (n = 1027) attitudes towards surgical castration without pain relief, surgical castration with anaesthesia, immunocastration, and production of boars were surveyed from April to June 2020 via an online questionnaire in 16 countries (>175 respondents per country). Surgical castration without pain relief was separated from each of the alternatives due to animal welfare and showed the lowest acceptability (32%). Within the alternatives, a further partitioning between the alternatives was based on perceived quality and food safety, with an acceptance of 85% for applying anaesthesia, 71% for immunocastration, and 49% for boar production. Differences depending on professional involvement and familiarity with agriculture could be observed, mainly for the acceptance of surgical castration without anaesthesia, immunocastration, and boars. Castration with anaesthesia was highly accepted by all types of respondents

Radioiodination via isotope exchange in pivalic acid

A variety of benzoic and aryl aliphatic mono and polyiodinated acids and esters (sterol, triglyceride) were radioiodinated in 55-99% radiochemical yield by isotope exchange with Na 125I in a melt of pivalic acid. In general, the reaction was complete in 1 h at 155[deg]C with little or no substrate decompostion. High specific activity studies afforded 125I-labeled iopanoic acid with a specific activity of over 700 Ci/mmol.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26445/1/0000533.pd