| 1. |
- Rydholm, H., et al.
(author)
-
Reducing Adverse Effects During Drug Development: The Example of Lesogaberan and Paresthesia
- 2016
-
In: Clinical Therapeutics. - : Elsevier BV. - 0149-2918. ; 38:4, s. 946-960
-
Journal article (peer-reviewed)abstract
- Purpose: Lesogaberan, a gamma-aminobutyric acid (GABA)(B) receptor agonist, was developed for the treatment of gastroesophageal reflux disease in patients with a partial response to proton pump inhibitor therapy. A high prevalence of paresthesia was observed in healthy individuals after dosing with lesogaberan in early-phase clinical trials. The aim of this review was to gain further insight into paresthesia caused by lesogaberan by summarizing the relevant preclinical and clinical data. Methods: This study was a narrative review of the literature and unpublished data. Findings: The occurrence of paresthesia may depend on the route or rate of drug administration; several studies were conducted to test this hypothesis, and formulations were developed to minimize the occurrence of paresthesia. Phase I clinical studies showed that, in healthy individuals, paresthesia occurred soon after administration of lesogaberan in a dose-dependent manner regardless of the route of administration. The occurrence of paresthesia could be decreased by fractionating the dose or reducing the rate of administration. These findings suggest that the initial rate of absorption plays an important part in the development of paresthesia. Modified-release formulations minimize the occurrence of paresthesia while retaining the anti-reflux activity of the drug, as measured by esophageal pH and the number of transient lower esophageal sphincter relaxations. Implications: The development of lesogaberan was halted because the effect on gastroesophageal reflux disease symptoms observed in Phase II studies was not considered clinically meaningful in the target patient population. Nevertheless, it is an example of successful formulation development designed to minimize the occurrence of a compound's adverse effect while retaining its pharmacodynamic action. (C) 2016 Elsevier HS Journals, Inc. All rights reserved.
|
|
| 2. |
- Doriese, W B, et al.
(author)
-
A practical superconducting-microcalorimeter X-ray spectrometer for beamline and laboratory science
- 2017
-
In: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 88:5
-
Journal article (peer-reviewed)abstract
- We describe a series of microcalorimeter X-ray spectrometers designed for a broad suite of measurement applications. The chief advantage of this type of spectrometer is that it can be orders of magnitude more efficient at collecting X-rays than more traditional high-resolution spectrometers that rely on wavelength-dispersive techniques. This advantage is most useful in applications that are traditionally photon-starved and/or involve radiation-sensitive samples. Each energy-dispersive spectrometer is built around an array of several hundred transition-edge sensors (TESs). TESs are superconducting thin films that are biased into their superconducting-to-normal-metal transitions. The spectrometers share a common readout architecture and many design elements, such as a compact, 65 mK detector package, 8-column time-division-multiplexed superconducting quantum-interference device readout, and a liquid-cryogen-free cryogenic system that is a two-stage adiabatic-demagnetization refrigerator backed by a pulse-tube cryocooler. We have adapted this flexible architecture to mate to a variety of sample chambers and measurement systems that encompass a range of observing geometries. There are two different types of TES pixels employed. The first, designed for X-ray energies below 10 keV, has a best demonstrated energy resolution of 2.1 eV (full-width-at-half-maximum or FWHM) at 5.9 keV. The second, designed for X-ray energies below 2 keV, has a best demonstrated resolution of 1.0 eV (FWHM) at 500 eV. Our team has now deployed seven of these X-ray spectrometers to a variety of light sources, accelerator facilities, and laboratory-scale experiments; these seven spectrometers have already performed measurements related to their applications. Another five of these spectrometers will come online in the near future. We have applied our TES spectrometers to the following measurement applications: synchrotron-based absorption and emission spectroscopy and energy-resolved scattering; accelerator-based spectroscopy of hadronic atoms and particle-induced-emission spectroscopy; laboratory-based time-resolved absorption and emission spectroscopy with a tabletop, broadband source; and laboratory-based metrology of X-ray-emission lines. Here, we discuss the design, construction, and operation of our TES spectrometers and show first-light measurements from the various systems. Finally, because X-ray-TES technology continues to mature, we discuss improvements to array size, energy resolution, and counting speed that we anticipate in our next generation of TES-X-ray spectrometers and beyond.
|
|
