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Two Students Talking Outdoors
No full textTwo C. W. Post students in conversation on campus.https://digitalcommons.liu.edu/post_early/1035/thumbnail.jp
C. W. Post Coach and Cheerleader
No full textC. W. Post Campus first Athletic Director Roy Illowit and student cheerleader.https://digitalcommons.liu.edu/post_early/1034/thumbnail.jp
Investigation of Percutaneous Drug Pharmacokinetics in Yucatan Mini-Pig Utilizing Microdialysis: Development of an In Vitro - In Vivo Relationship with Metronidazole Topical Dermatological Drug Products
Get PDFThe use of dermal microdialysis (dMD) to evaluate bioavailability (BA) and bioequivalence (BE) of topical dermatological drug products (TDDP) has shown promising results; however, studies conducted thus far have been inconclusive conceivably due to large inter- and intra-subject variability, in addition to the inability of short experiments to completely characterize the dermis pharmacokinetics (PK). By using multiple test sites on the same subject, and replicate probes at each test site, it is feasible to compare the dermal pharmacokinetics (dPK) of a drug from different products in parallel on the same subject, which in turn will help to control variability. Moreover, increasing the duration of the experiments to detect the terminal phase, would allow a better comparison between products. However, there are technical considerations related to the dMD experimental design that must be characterized and optimized to ensure that the in vivo dMD study is selective, sensitive, discriminating, reproducible and that the dMD probe performs consistently for the entire duration of the experiments. Studies were conducted in Yucatan mini-pigs using a generic cream (0.75%) and a generic gel (0.75%) formulation of the drug Metronidazole (MTZ) with known different In-Vitro Permeation Testing (IVPT) data profiles. MTZ is a small, water soluble molecule, with low protein binding. Thus, it is an ideal substrate to challenge the dMD technique. The goals of the first set of Yucatan mini-pig studies were to assess: (i) the minimum distance required between test sites to prevent cross-talk between probes (due to potential lateral diffusion of drug in the dermis from a different test site); (ii) the sensitivity of the dMD method to detect differences in the local concentration of the drug, which was modulated by applying different doses of the topical product (3, 10, and 30 mg/cm2); (iii) the stability of dMD probe sampling over the 48-hour study duration. The results of these study showed negligible lateral diffusion and undetectable systemic redistribution suggesting that the MTZ concentrations measured by the dMD probes can be specifically associated with the local bioavailability from the topical dose of the cream or gel, at that specific application site. The results also indicated that the dMD method was sensitive to differences in the in vivo topical bioavailability of MTZ from each product, and selective to differences in bioavailability between cream and gel products of the same strength. Although studies were 48 hours long, the terminal phase was still non-identifiable. Therefore, a second set of Yucatan mini pig studies were conducted with the goal to assess the effect of application-time (AT) on dermis exposure, which may be a possible strategy to shorten the length of an experiment and obtain an estimate of the terminal phase. The dPK from the dose of 10 mg/cm2 of the two, previously used, MTZ topical dermatological formulations applied for 6 hours and 12 hours was compared to non-removal (48-hr-AT). Total exposure from the gel formulation was independent of the application time, suggesting that most of the drug had permeated within 6 hours. Conversely, for the cream formulation, the exposure resulting from the 6-hr-AT was significantly lower than that with 12-hr-AT (p = 0.026) and 48-hr-AT (p = 0.006), suggesting that absorption into the skin from the cream is complete by 12-hr. However, dermis concentrations increased for an additional 6-8 hours suggesting that MTZ from the upper layers of the skin continue to reach the dermis after formulation removal. In this experiment, two additional dMD probes were inserted at a site distant from the formulations and were perfused with a known concentration of MTZ solution (retrodialysis phase). The perfusion solution was then switched to plain lactated Ringer’s solution (microdialysis phase) to estimate MTZ dermis elimination. Differences between terminal half-life at formulation sites and formulation-independent elimination t. suggests a flip/flop PK scenario. Data from these probes were used to estimate the dermis unit impulse response (dUIR). In vivo flux and in vivo cumulative amount permeated were estimated by deconvolution, for each formulation and AT, from the observed PK profiles with the dUIR. Comparison of these in vivo dMD data with in vitro permeation testing (IVPT) data led to the development of a Level A in vitro-in vivo relationship (IVIVR). The results of these studies further confirm the capability of the microdialysis technique to capture differences in the rate and extent of dermis absorption from topical dermatological formulations. In addition, availability of an IVIVR can help to streamline the development of generic TDDP and possibly reduce the cost of bringing a generic to market; however, more investigation must be done into the assumptions for this IVIVR approach
A Fine Pair of Wheel-Lock Pistols
No full textThe stocks of walnut-wood richly inlaid with a design of birds and animals in engraved ivory and mother-of-pearl. From the Beardmore Collection. Provenance: Purchased by William Randolph Hearst from Christie, Manson and Woods, through Duveen Brothers, London, England January 23, 1922 for 289.https://digitalcommons.liu.edu/post_hearst/1223/thumbnail.jp
An Extraordinary Flintlock Hunting Rifle
No full textOctagonal iron barrel mounted on beautifully carved walnut guard and stock, in which are incorporated very fine carved ivory panels depicting various mythological scenes. One of the panels also includes Coat-of-arms surmounted with coronet of Prince. The gun is further embellished by the patine of the wood and the ivory. Provenance: Purchased by William Randolph Hearst from P.W. French & Co., March 26, 1921 for 500; sold to Gimbel Bros., Inc., April 30, 1941 for $1078.https://digitalcommons.liu.edu/post_hearst/1215/thumbnail.jp
Napoleon\u27s Gun
No full textA flint-lock Sporting Rifle, with gold and silver furniture, safety rigger, silver-mounted whalebone rod, and spring bayonet. The gun was used by Napoleon, and, apart from its great historical interest, is remarkable as a very early form of flint-lock rifle. It belonged for many years to Egg, the famous gun-maker, whose private collection contained only guns of exceptional interest. Provenance: Purchased by William Randolph Hearst from the Maund Collection Sale, Sotheby, Wilkinson & Hodge, June 13, 1913, through William Permain, July 14, 1913 for $689.79; sold to Gimbel Bros., Inc., May 26, 1941 for 209.https://digitalcommons.liu.edu/post_hearst/1214/thumbnail.jp
Combination Axe, Pistol and Dagger
No full textThe axe-head is a decorative scroll. Flintlock pistol. The handle is the sheath for a long four-sided stiletto. The handle is finely inlaid with ivory figures and scrolls. From the Meyrick Collection. From the Magniac Collection. Provenance: Purchased by William Randolph Hearst from The Sam Austin Sale, American Art Galleries through The American Art Association, Inc., April 24-28, 1917 for 98.https://digitalcommons.liu.edu/post_hearst/1261/thumbnail.jp
A Wheel-Lock Rifle
No full textBarrel 39.4 inches long; calibre .65 of an inch; octagonal; at breech engraved with tendrils and foliation, where the initials M. S. occur, also owner\u27s stamp at side of barrel, the royal crown above monogram C. L. Lock of high quality workmanship, enriched everywhere with engraving; on hammer fire-dragon\u27s head...the two major themes of composition on single plates of ivory are Diana as musician charming the unicorn, and on cover, of pyrites-holder Diana sounding her horn. Double-headed eagle engraved on the butt-plate. Note: The artist signing his initials M.S. is doubtless Martin Sussebecker, b. in Liegnitz 1593, d. 1668 in Dresden. Provenance: Purchased by William Randolph Hearst from the European Arms and Armor Sale at American Art Association, Nov. 20, 1926 for 1050.https://digitalcommons.liu.edu/post_hearst/1253/thumbnail.jp
Two Wheel-Lock Cavalry Pistols
No full textArticle 58 has a round barrel with center rib, lock of bright steel, and wheel concealed. Article 59 has an octagonal barrel, lock of bright steel, and wheel exposed. The stocks of both pistols are of a light color in walnut. Provenance: Purchased by William Randolph Hearst through Archduke Eugen Sale from Anderson Galleries, March 7, 1927 for 100.https://digitalcommons.liu.edu/post_hearst/1235/thumbnail.jp
A Fine Wheel-Lock Tschinke
No full textOf delicate construction, the cock chiseled and engraved, exposed mainspring with pierced cover, the stock inlaid with buck-horn and pearl. Provenance: Purchased by William Randolph Hearst from Sotheby & Co., London, June 20, 1929.https://digitalcommons.liu.edu/post_hearst/1177/thumbnail.jp