The Stability of Insulin in Crystalline and Amorphous Solids: Observation of Greater Stability for the Amorphous Form Tập 14 Số 10 - Trang 1379-1387 - 1997
Pikal, Michael J., Rigsbee, Daniel R.
Purpose. Generalizations based upon behavior of small molecules have established that a crystalline solid is generally much more stable toward chemical degradation than is the amorphous solid. This study examines the validity of this generalization for proteins using biosynthetic human insulin as the model protein. Methods. Amorphous insulin was prepared by freeze drying the supernate from a suspe...... hiện toàn bộ
The Oral Absorption of Micro- and Nanoparticulates: Neither Exceptional Nor Unusual Tập 14 Số 3 - Trang 259-266 - 1997
Florence, Alexander T.
This mini-review covers some of the historical and recent arguments over the experimental evidence on the uptake by and translocation from the intestinal mucosa of microparticulates after oral administration. It is concluded that there is now no dispute over the fact that this is a normal occurrence. Particulate uptake does take place, not only via the M-cells in the Peyer's patches and the isolat...... hiện toàn bộ
Improvement of the Pulmonary Absorption of (Asu1,7)-Eel Calcitonin by Various Protease Inhibitors in Rats Tập 11 Số 6 - Trang 909-913 - 1994
Morita, Takahiro, Yamamoto, Akira, Takakura, Yoshinobu, Hashida, Mitsuru, Sezaki, Hitoshi
The effects of protease inhibitors, Na-glycocholate, bacitracin, bestatin, nafamostat mesilate and soybean trypsin inhibitor (STI) on the pulmonary absorption of (Asu1,7)-eel calcitonin (ECT, molecular weight 3363) were investigated in rats. The pulmonary absorption of ECT was estimated by measuring its hypocalcemic effect. When ECT alone was administered into the lung, the pharmacological availab...... hiện toàn bộ
Proteolysis of Human Calcitonin in Excised Bovine Nasal Mucosa: Elucidation of the Metabolic Pathway by Liquid Secondary lonization Mass Spectrometry (LSIMS) and Matrix Assisted Laser Desorption lonization Mass Spectrometry (MALDI) Tập 13 Số 11 - Trang 1679-1685 - 1996
Lang, Steffen R., Staudenmann, Werner, James, Peter, Manz, Hans-Jörg, Kessler, Rudolf, Galli, Bruno, Moser, Hans-Peter, Rummelt, Andreas, Merkle, Hans P.
Purpose. Two calcitonins, i.e. human calcitonin (hCT) and, for comparison, salmon calcitonin (sCT), were chosen as peptide models to investigate nasal mucosal metabolism. Methods. The susceptibility of hCT and sCT to nasal mucosal enzymes was assessed by in-and-out reflection kinetics experiments in an in vitro model based on the use of freshly excised bovine nasal mucosa, with the mucosal surface...... hiện toàn bộ
Photo-Oxidation Mechanisms in Liquid Pharmaceutical Formulations: The Overlooked Role of Singlet Oxygen Presented as a Case Study - 2022
Brunell, Margaret, Tignor, Steven, Pierson, Elizabeth, Walsh, Paul L.
Oxidation is one of the most common degradation pathways for active pharmaceutical ingredients (APIs) in pharmaceutical formulations, mostly involving 1-electron processes via peroxy radicals and 2-electron processes by peroxides. In liquid pharmaceutical formulations, several factors can impact oxidative instabilities including pH, excipient impurities, headspace oxygen, and the potential for pho...... hiện toàn bộ
Comparison of the Anticancer Effect of Free and HPMA Copolymer-Bound Adriamycin in Human Ovarian Carcinoma Cells Tập 16 Số 7 - Trang 986-996 - 1999
Minko, Tamara, Kopečková, Pavla, Kopeček, Jindřich
Purpose. To study peculiarities and the mechanism of the anticancer effect of free and HPMA copolymer-bound ADR in sensitive and resistant human ovarian carcinoma cells. Methods. Sensitive A2780 and ADR resistant A2780/AD cells were exposed to different doses of drugs during 12, 24, 36, 48, 60, and 72 hours. Cell viability, drug accumulation, apoptosis, cellular metabolism, lipid peroxidation, DNA...... hiện toàn bộ
Development of New Lipophilic Derivatives of Tetragastrin: Physicochemical Characteristics and Intestinal Absorption of Acyl-tetragastrin Derivatives in Rats Tập 10 Số 10 - Trang 1488-1492 - 1993
Tenma, Takehiro, Yodoya, Etsuo, Tashima, Shigeru, Fujita, Takuya, Murakami, Masahiro, Yamamoto, Akira, Muranishi, Shozo
In order to improve the intestinal absorption of tetragastrin (TG), we synthesized lipophilic derivatives of TG by acylation of its N-terminal amino group with acetic acid, caproic acid, and lauric acid. The purified TG derivatives, acetyl-tetragastrin (Ac-TG), caproyl-tetragastrin (Cap-TG), and lauroyl-tetragastrin (Lau-TG), were confirmed to be more lipophilic than the parent TG by high-performa...... hiện toàn bộ