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Automation of a Positron-emission Tomography (PET) Radiotracer Synthesis Protocol for Clinical Production.
The development of new positron-emission tomography (PET) tracers is enabling researchers and clinicians to image an increasingly wide array of biological targets and processes. However, the increasing number of different tracers creates challenges for their production at radiopharmacies. While historically it has been practical to dedicate a custom-configured radiosynthesizer and hot cell for the repeated production of each individual tracer, it is becoming necessary to change this workflow. Recent commercial radiosynthesizers based on disposable cassettes/kits for each tracer simplify the production of multiple tracers with one set of equipment by eliminating the need for custom tracer-specific modifications. Furthermore, some of these radiosynthesizers enable the operator to develop and optimize their own synthesis protocols in addition to purchasing commercially-available kits. In this protocol, we describe the general procedure for how the manual synthesis of a new PET tracer can be automated on one of these radiosynthesizers and validated for the production of clinical-grade tracers. As an example, we use the ELIXYS radiosynthesizer, a flexible cassette-based radiochemistry tool that can support both PET tracer development efforts, as well as routine clinical probe manufacturing on the same system, to produce [18F]Clofarabine ([18F]CFA), a PET tracer to measure in vivo deoxycytidine kinase (dCK) enzyme activity. Translating a manual synthesis involves breaking down the synthetic protocol into basic radiochemistry processes that are then translated into intuitive chemistry "unit operations" supported by the synthesizer software. These operations can then rapidly be converted into an automated synthesis program by assembling them using the drag-and-drop interface. After basic testing, the synthesis and purification procedure may require optimization to achieve the desired yield and purity. Once the desired performance is achieved, a validation of the synthesis is carried out to determine its suitability for the production of the radiotracer for clinical use
Privacy policy violations: A corporate nexus of healthcare providers and social media platforms
When healthcare information is shared on social media, who’s to blame? It can be difficult for users to determine whether it was the social media platform or the healthcare provider that caused the privacy violation. A model of behavioral intentions following a privacy breach on a social media platform is developed in which perceptions of psychological contract violations for both entities determine multiple response intentions
Sleep Education for Elders Program (SLEEP): Promising Pilot Results of a Virtual, Health Educator-Led, Community-Delivered Sleep Behavior Change Intervention
Purpose: Sleep problems pose serious public health concerns, and evidence suggests that the problem is worsening. Both sufficient sleep quantity and quality are needed for optimal health, particularly among older adults, but access to sleep care can be difficult. This study examined the efficacy of a six-week sleep behavior change program designed for older adults that was delivered virtually by health educators.
Participants and Methods: This quasi-experimental pilot study (intervention n = 22; control n = 31) explored the effects of the Sleep Education for Elders Program (SLEEP) on sleep outcomes, which included: 1) sleep quality, measured by the Pittsburgh Sleep Quality Index (PSQI); 2) sleep duration, extracted from the PSQI; 3) insomnia symptoms, measured by the Insomnia Severity Index; 4) sleep hygiene behaviors, obtained from the Sleep Hygiene Index; and 5) excessive daytime sleepiness, measured by the Epworth Sleepiness Scale.
Results: After SLEEP, the intervention group experienced significantly improved sleep quality (p \u3c 0.001), a reduction in maladaptive sleep hygiene behaviors (p = 0.007), and reduced daytime sleepiness (p \u3c 0.027) compared to the control group. Effect sizes for all five sleep measures were medium or large. In the intervention group, all changes were judged to be clinically meaningful (≥ 0.5 SD) except for improvements in daytime sleepiness.
Conclusion: These data support the efficacy of a group-based, virtual behavior change intervention in improving sleep outcomes among older adults
The anxiolytic effects of cognitive behavior therapy for insomnia: preliminary results from a web-delivered protocol
Though the efficacy of cognitive behavior therapy for insomnia (CBTI) is well-established, the paucity of credentialed providers hinders widespread access. Further, the impact of alternatives such as web-delivered CBTI has not been adequately tested on common insomnia comorbidities such as anxiety. Therefore, we assessed the impact of an empirically validated web-delivered CBTI intervention on insomnia and comorbid anxiety symptoms. A sample of 22 adults (49.8±13.5 yo; 62.5% female) with DSM-5 based insomnia were randomized to either an active CBTI treatment group (n = 13) or an information-control (IC) group (n = 9). Participants in the CBTI group underwent a standard CBTI program delivered online by a 'virtual' therapist, whereas the IC group received weekly 'sleep tips' and general sleep hygiene education via electronic mail. All participants self-reported sleep parameters, including sleep onset latency (SOL), insomnia symptoms per the Insomnia Severity Index (ISI), and anxiety symptoms per the Beck Anxiety Inventory (BAI) at both baseline as well as follow- up assessment one week post-treatment. There were no significant differences between the CBTI and IC groups on baseline measures. The CBTI group showed significantly larger reductions in BAI scores (t = 2.6; p < .05; Cohen's d = .8) and ISI scores (t = 2.1; p < .05; Cohen's d = .9) at follow-up than did the IC group. Further, changes in SOL from baseline (62.3±44.0 minutes) to follow-up (22.3±14.4 minutes) in the CBTI group were also significantly greater (t = 2.3; p < .05; Cohen's d = .9) than in the IC group (baseline: 55.0±44.2 minutes; follow-up: 50.±60.2 minutes).This study offers preliminary evidence that a web-delivered CBTI protocol with minimal patient contact can improve comorbid anxiety symptoms among individuals with insomnia
Immunomodulation and T Helper TH1/TH2 Response Polarization by CeO2 and TiO2 Nanoparticles
Immunomodulation by nanoparticles, especially as related to the biochemical properties of these unique materials, has scarcely been explored. In an in vitro model of human immunity, we demonstrate two catalytic nanoparticles, TiO2 (oxidant) and CeO2 (antioxidant), have nearly opposite effects on human dendritic cells and T helper (T-H) cells. For example, whereas TiO2 nanoparticles potentiated DC maturation that led towards T(H)1-biased responses, treatment with antioxidant CeO2 nanoparticles induced APCs to secrete the anti-inflammatory cytokine, IL-10, and induce a T(H)2-dominated T cell profile. In subsequent studies, we demonstrate these results are likely explained by the disparate capacities of the nanoparticles to modulate ROS, since TiO2, but not CeO2 NPs, induced inflammatory responses through an ROS/inflammasome/IL-1 beta pathway. This novel capacity of metallic NPs to regulate innate and adaptive immunity in profoundly different directions via their ability to modulate dendritic cell function has strong implications for human health since unintentional exposure to these materials is common in modern societies
Immunomodulation and T Helper TH1/TH2 Response Polarization by CeO2 and TiO2 Nanoparticles
Immunomodulation by nanoparticles, especially as related to the biochemical properties of these unique materials, has scarcely been explored. In an in vitro model of human immunity, we demonstrate two catalytic nanoparticles, TiO2 (oxidant) and CeO2 (antioxidant), have nearly opposite effects on human dendritic cells and T helper (T-H) cells. For example, whereas TiO2 nanoparticles potentiated DC maturation that led towards T(H)1-biased responses, treatment with antioxidant CeO2 nanoparticles induced APCs to secrete the anti-inflammatory cytokine, IL-10, and induce a T(H)2-dominated T cell profile. In subsequent studies, we demonstrate these results are likely explained by the disparate capacities of the nanoparticles to modulate ROS, since TiO2, but not CeO2 NPs, induced inflammatory responses through an ROS/inflammasome/IL-1 beta pathway. This novel capacity of metallic NPs to regulate innate and adaptive immunity in profoundly different directions via their ability to modulate dendritic cell function has strong implications for human health since unintentional exposure to these materials is common in modern societies
Cardiovascular safety in refractory incontinent patients with overactive bladder receiving add-on mirabegron therapy to solifenacin (BESIDE)
© 2017 John Wiley & Sons Ltd.Summary : Aims/objectives: : In the BESIDE study, combination therapy (antimuscarinic [solifenacin] and β3-adrenoceptor agonist [mirabegron]) improved efficacy over solifenacin monotherapy without exacerbating anticholinergic side effects in overactive bladder (OAB) patients; however, a potential synergistic effect on the cardiovascular (CV) system requires investigation. Methods: OAB patients remaining incontinent despite daily solifenacin 5 mg during 4-week single-blind run-in, were randomised 1:1:1 to double-blind daily combination (solifenacin 5 mg/mirabegron 25 mg, increasing to 50 mg after week 4), solifenacin 5 or 10 mg for 12 weeks. CV safety assessments included frequency of CV-related treatment-emergent adverse events (TEAEs), change from baseline in vital signs (systolic blood pressure [SBP], diastolic blood pressure [DBP], pulse rate) and electrocardiogram (ECG) parameters. Results: The frequency of hypertension, tachycardia and ECG QT prolongation, respectively, was low and comparable across combination (1.1%, 0.3%, 0.1%), solifenacin 5 mg (0.7%, 0.1%, 0.1%), and solifenacin 10 mg groups (0.8%, 0%, 0.1%). Adjusted mean (SE) change from baseline to end of treatment (EoT) in SBP, DBP, and pulse rate with combination (0.07 mm Hg [0.38], -0.35 mm Hg [0.26], 0.47 bpm [0.28]), solifenacin 5 mg (-0.93 mm Hg [0.38], -0.45 mm Hg [0.26], 0.43 bpm [0.28]) and solifenacin 10 mg (-1.28 mm Hg [0.38], -0.48 mm Hg [0.26], 0.27 bpm [0.28]) was generally comparable, with the exception of a mean treatment difference of ~1 mm Hg in SBP between combination and solifenacin monotherapy; SBP was unchanged with combination and decreased with solifenacin monotherapy. Mean changes from baseline to EoT in ECG parameters were generally similar across treatment groups, except for QT interval corrected using Fridericia's formula, which was higher with solifenacin 10 mg (3.30 mseconds) vs. combination (0.49 mseconds) and solifenacin 5 mg (0.77 mseconds). Conclusion: The comparable frequency of CV-related TEAEs, changes in vital signs and ECG parameters indicates no synergistic effect on CV safety outcomes when mirabegron and solifenacin are combined
TGF-β receptor expression and binding in rat mesangial cells: Modulation by glucose and cyclic mechanical strain
TGF-β receptor expression and binding in rat mesangial cells: Modulation by glucose and cyclic mechanical strain.BackgroundTransforming growth factor-β (TGF-β) is a causal factor in experimental glomerulosclerosis, and it mediates the increased extracellular matrix (ECM) accumulation that occurs in cultured mesangial cells (MCs) exposed to high glucose concentrations and cyclic mechanical strain. This change is associated with increased levels of TGF-β, but may also involve alterations in receptor expression and binding.MethodsRat MCs cultured in media containing either 8 or 35 mM glucose were seeded into culture plates with elastin-coated flexible bottoms. Thereafter, they were subjected to cyclic stretch or static conditions and then examined for125I-TGF-β1 binding and expression of TGF-β receptors at the gene and protein levels.ResultsKinetic studies showed that MCs bound TGF-β1 in a time- and concentration-dependent manner, expressing 6800 high-affinity receptors per cell, with an apparent dissociation constant (Kd) of 15.4 pM, while cross-linking analysis identified three TGF-β receptors (βR) corresponding to βRI, βRII, and βRIII of 54, 73, and 200 kDa, respectively. Immunocytochemical studies of βRI and βRII protein revealed MC expression in a homogeneous, punctate distribution, whereas Northern analysis demonstrated the presence of the corresponding mRNAs. Exposure to cyclic stretching significantly increased (10%) the overall number of TGF-β receptors, whereas ligands associated with βRs I, II, and III also increased (25 to 50%). The finding of increased (30 to 40%) βRI and βRII transcript levels and immunoreactive protein (163 and 59%, respectively) in the absence of significant changes in the apparent Kd indicated that stretch-induced binding was the result of increased receptor synthesis and expression and not due to a change in binding affinity. In a similar, but more dramatic fashion, exposure to high glucose also elevated (50%) the receptor number, as well as the amount of ligands associated with βRs I, II, and III (100 to 250%). This same treatment also increased the levels of βRI and βRII mRNA (30 to 40%) and the immunoreactive protein (82 and 82%, respectively), without significantly altering the binding affinity of the receptor. A concerted or synergistic effect of both stimuli was not evidenced.ConclusionThese results suggest that the modulation of TGF-β receptors may be an additional control point in mediating the glucose- and mechanical force-induced increase in ECM deposition by MCs
Thermal Emission and Tidal Heating of the Heavy and Eccentric Planet XO-3b
We determined the flux ratios of the heavy and eccentric planet XO-3b to its
parent star in the four IRAC bands of the Spitzer Space Telescope: 0.101% +-
0.004% at 3.6 micron; 0.143% +- 0.006% at 4.5 micron; 0.134% +- 0.049% at 5.8
micron and 0.150% +- 0.036% at 8.0 micron. The flux ratios are within
[-2.2,0.3, -0.8, -1.7]-sigma of the model of XO-3b with a thermally inverted
stratosphere in the 3.6 micron, 4.5 micron, 5.8 micron and 8.0 micron channels,
respectively. XO-3b has a high illumination from its parent star (Fp ~(1.9 -
4.2) x 10^9 ergs cm^-2 s^-1) and is thus expected to have a thermal inversion,
which we indeed observe. When combined with existing data for other planets,
the correlation between the presence of an atmospheric temperature inversion
and the substellar flux is insufficient to explain why some high insolation
planets like TrES-3 do not have stratospheric inversions and some low
insolation planets like XO-1b do have inversions. Secondary factors such as
sulfur chemistry, atmospheric metallicity, amounts of macroscopic mixing in the
stratosphere or even dynamical weather effects likely play a role. Using the
secondary eclipse timing centroids we determined the orbital eccentricity of
XO-3b as e = 0.277 +- 0.009. The model radius-age trajectories for XO-3b imply
that at least some amount of tidal-heating is required to inflate the radius of
XO-3b, and the tidal heating parameter of the planet is constrained to Qp <
10^6 .Comment: Accepted for publications in The Astrophysical Journa
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