Use of Time-Domain NMR for 1H T1 Relaxation Measurement and Fitting Analysis in Homogeneity Evaluation of Amorphous Solid Dispersion.

This study examined the usefulness of 1H T1 relaxation measurements for evaluating the homogeneity of amorphous solid dispersion (ASD). Indomethacin and polyvinylpyrrolidone were used to prepare two kinds of ASDs. One was inhomogeneous ASD (ASDmelt) prepared by a melt-quenching method, and the other was homogeneous ASD (ASDsolvent) prepared by a solvent evaporation method. The T1 relaxation was measured by the time-domain NMR (TD-NMR) technique using a low-field NMR system. Curve-fitting analysis of T1 relaxation plots was conducted using the Akaike information criterion. This fitting analysis revealed that the T1 relaxation of ASDmelt and ASDsolvent was biphasic and monophasic, respectively. ASDmelt and ASDsolvent were inhomogeneous and homogeneous on a nanometer scale, respectively, considering the spin diffusion of 1H nuclei. These T1 results were consistent with the Raman mapping of ASDs. From the fitting analysis of 1H T1 relaxation, we conclude that TD-NMR is a promising technique for evaluating ASD homogeneity.

Adult axillary lymphangioma removal using indocyanine green fluorescence imaging system: A case report.

INTRODUCTION: Lymphangiomas are benign cystic tumors which arise from congenital malformations of the lymphatic system and are extremely rare in adulthood. We report a case of adult lymphangioma of the axilla that was removed after identifying the feeding lymphatic vessel using an indocyanine green (ICG) fluorescence imaging system. PRESENTATION OF CASE: A 35-year old woman presented to our hospital with a rapidly growing mass on her left axilla. She had been pregnant once before and delivered at 34 years of age. Mammography, ultrasonography, and magnetic resonance imaging revealed a tumor that consisted of multiple cysts, which led to a diagnosis of cystic lymphangioma. The ICG fluorescence imaging system indicated that only one lymphatic vessel, which was completely removed with ligation of the feeding lymphatic vessel, was flowing to the tumor. An immunohistological study demonstrated that the cystic endothelia were positive for podoplanin (D2-40), a marker of lymphatic vessels. DISCUSSION: In addition to congenital factors, mechanical obstruction to lymphatic vessels by an external force, such as trauma or congestion of the lymphatic flow caused by increasing venous pressure during pregnancy or delivery might lead to lymphangioma in adulthood. Therefore, our patient's pregnancy and delivery one year prior to discovery of the tumor seems to be the cause of her lymphangioma. CONCLUSION: Based on our findings, we recommend the complete excision to successfully treat adult-onset lymphangioma. We also suggest that visualization with ICG fluorescence imaging system is very useful for detecting the feeding lymphatic vessel and performing complete excision of the lymphangioma.

1H NMR Relaxation Study to Evaluate the Crystalline State of Active Pharmaceutical Ingredients Containing Solid Dosage Forms Using Time Domain NMR.

The aim of this study was to demonstrate the usefulness of the time domain nuclear magnetic resonance (TD-NMR) method to characterize the crystalline state of active pharmaceutical ingredients (APIs) containing solid dosage forms. In this study, carbamazepine and indomethacin are used as models for poorly water-soluble APIs. First, we measured the T1 and T2 relaxation behavior of crystalline and amorphous APIs. From the results, we were able to confirm that the T1 relaxation time measured by TD-NMR is an effective parameter for distinguishing between crystalline and amorphous states in powdered APIs. We then examined physical mixtures of APIs with polyvinylpyrrolidone and their solid dispersion. The results indicated that TD-NMR allows the evaluation of not only the crystalline form of APIs but also the miscibility of APIs and polymers. In the final phase of the study, we conducted continuous monitoring of the crystalline state of APIs incorporated into physical mixtures during the thermal stress test. Conversion to crystalline forms of the APIs was successfully monitored based on the T1 relaxation behavior. Our findings led us to conclude that TD-NMR is useful as a new approach to evaluate the crystalline state of APIs.

Inhibition of Gastric H+,K+-ATPase Activity in Vitro by Dissolution Media of Original Brand-Name and Generic Tablets of Lansoprazole, a Proton Pump Inhibitor.

To investigate the inhibitory effect of a commercial proton pump inhibitor (lansoprazole) on the gastric proton pump H+,K+-ATPase in vitro, we used orally disintegrating (OD) tablets including original brand-name and generic tablets. In the course of the development of generic products, dissolution and clinical tests are necessary to ensure their bioequivalence to the original brand-name products; by contrast, there is almost no opportunity to demonstrate their activity in vitro. This study initially compared the similarity of the dissolution of test generic tablets with that of the original brand-name tablets. The dissolution tests for 15 and 30-mg lansoprazole tablets found their dissolution properties were similar. Subsequently, the dissolution media were sampled and then their effects on the H+,K+-ATPase activity were measured using tubulovesicles prepared from the gastric mucosa of hogs. We confirmed that the inhibitory effects of the generic tablets on H+,K+-ATPase activity were consistent with those of the original brand-name tablets. Furthermore, lansoprazole contents in each tablet estimated from their inhibitory effects were in good agreement with their active pharmaceutical ingredient content. To our knowledge, this is the first technical report to compare the in vitro biochemical activity of lansoprazole OD tablets between the original brand-name and generic commercial products.

Mixtures of betamethasone butyrate propionate ointments and heparinoid oil-based cream: Physical stability evaluation.

Betamethasone butyrate propionate ointment (BBPO) is mainly used for adult patients in dermatology and is often prescribed as a mixture containing a base or moisturizing cream for various reasons. However, in the case of a moisturizing cream, since this formulation is composed of various ingredients, a physical change is expected to occur by mixing it with an ointment. Therefore, in the present study, the physical stability of a mixture of four BBPO formulations and heparinoid oily cream (HPOC) was examined. Layer separation was observed in all mixtures following centrifugation. The near-infrared (NIR) measurement showed a peak at 5200 cm-1 on the lower layer side, which strongly suggests the presence of water. The peak at 5200 cm-1 in the middle layer was hardly observed in the mixtures of two BBPO generic formulations and HPOC, thus suggesting that the separation was more advanced in those mixtures than in the others. These two mixtures separated into a semisolid layer (upper side) and a liquid layer (lower side) after 3 h of storage at 37 °C. The NIR measurement of each layer revealed that most of the semisolid layer was oil while the liquid layer was water. Furthermore, backscattered light measurements were conducted to monitor the behavior of the mixture's layer separation. An evaluation using model formulations revealed that the layer separation of the mixtures was due to the propylene glycol (PG) and surfactant content of the two generic BBPO formulations. Thus, these findings suggest that excipients need to be considered in selecting formulations for mixtures of skin preparations.

Non-destructive monitoring of creaming of oil-in-water emulsion-based formulations using magnetic resonance imaging.

A non-destructive method for monitoring creaming of emulsion-based formulations is in great demand because it allows us to understand fully their instability mechanisms. This study was aimed at demonstrating the usefulness of magnetic resonance (MR) techniques, including MR imaging (MRI) and MR spectroscopy (MRS), for evaluating the physicochemical stability of emulsion-based formulations. Emulsions that are applicable as the base of practical skin creams were used as test samples. Substantial creaming was developed by centrifugation, which was then monitored by MRI. The creaming oil droplet layer and aqueous phase were clearly distinguished by quantitative MRI by measuring T1 and the apparent diffusion coefficient. Components in a selected volume in the emulsions could be analyzed using MRS. Then, model emulsions having different hydrophilic-lipophilic balance (HLB) values were tested, and the optimal HLB value for a stable dispersion was determined. In addition, the MRI examination enables the detection of creaming occurring in a polyethylene tube, which is commonly used for commercial products, without losing any image quality. These findings strongly indicate that MR techniques are powerful tools to evaluate the physicochemical stability of emulsion-based formulations. This study will make a great contribution to the development and quality control of emulsion-based formulations.

[Efficacy of high-dose toremifene as a second-line hormone therapy in patients with advanced or metastatic breast cancer resistant to aromatase inhibitor].

BACKGROUND: Aromatase inhibitors(AIs)are frequently employed for advanced or metastatic postmenopausal breast cancer as first-line hormone therapy. However, it is unknown which hormonal agent is the most appropriate after AI has failed. PATIENTS AND METHODS: Five hormone-responsive postmenopausal women who used AI as a first-line hormone therapy for advanced or metastatic breast cancer, but AI failed, received high-dose toremifene therapy(HD-TOR: 120mg/day)in our hospital. Efficacy and safety were evaluated. RESULTS: Patients were all-hormone sensitive, and only one case had HER2 overexpression. All patients had received anastrozole(ANA)as first-line hormone therapy. Of a total of 5 cases, 3 were evaluated as partial responses(PR), 1 was a long stable disease(L-SD), and 1 was a progressive disease(PD). The overall response rate (RR)was 60. 0%(3/5 cases)and the clinical benefit rate(CB)was 80. 0%(4/5 cases). Grade 1 dry mouth was observed in one case as an adverse event. CONCLUSIONS: HD-TOR as a second-line therapy is optimal for advanced or metastatic AI resistance postmenopausal breast cancer.

Noninvasive visualization of in vivo release and intratumoral distribution of surrogate MR contrast agent using the dual MR contrast technique.

A direct evaluation of the in vivo release profile of drugs from carriers is a clinical demand in drug delivery systems, because drug release characterized in vitro correlates poorly with in vivo release. The purpose of this study is to demonstrate the in vivo applicability of the dual MR contrast technique as a useful tool for noninvasive monitoring of the stability and the release profile of drug carriers, by visualizing in vivo release of the encapsulated surrogate MR contrast agent from carriers and its subsequent intratumoral distribution profile. The important aspect of this technique is that it incorporates both positive and negative contrast agents within a single carrier. GdDTPA, superparamagnetic iron oxide nanoparticles, and 5-fluorouracil were encapsulated in nano- and microspheres composed of poly(D,L-lactide-co-glycolide), which was used as a model carrier. In vivo studies were performed with orthotopic xenograft of human breast cancer. The MR-based technique demonstrated here has enabled visualization of the delivery of carriers, and release and intratumoral distribution of the encapsulated positive contrast agent. This study demonstrated proof-of-principle results for the noninvasive monitoring of in vivo release and distribution profiles of MR contrast agents, and thus, this technique will make a great contribution to the field.

Displacement of tight junction proteins from detergent-resistant membrane domains by treatment with sodium caprate.

We have investigated the effect of sodium salt of capric acid (C10) on major tight junction proteins such as claudin and occludin, and also examined the involvement of lipid rafts with C10-induced alterations on these proteins. We firstly examined the C10 effect on the barrier function of tight junctions by measuring transepithelial electrical resistance (TER) and the flux of FITC dextran 4400 (FD-4). As a result, the increase in the FD-4 flux and decrease in the TER value were observed by incubation with C10 (10 mM) for 30 min, suggesting loss of the barrier function. In addition, C10 incubation produced an increase in solubility to Triton X-100 for claudin 4, 5 and occludin but not for claudin 1, 2, 3. Since it has been reported lipid raft disruption causes an increase in Triton X-100 solubility, it is suggested that effect of C10 on these proteins are involved with lipid rafts. From the lipid raft isolation study, we clarified the distribution of these proteins in lipid rafts. These results strongly indicate the displacement of specific tight junction proteins, claudin 4, 5 and occludin, from lipid raft by the treatment with C10 and involvement of this displacement with the absorption enhancing mechanism of C10.

Formulation optimization of water-in-oil-water multiple emulsion for intestinal insulin delivery.

Formulation optimization of the water-in-oil-in-water multiple emulsion incorporating insulin was performed based on statistical methods such as the orthogonal experimental design and the response surface evaluation. As model formulations, 16 types of emulsions were prepared according to the orthogonal experimental design. To optimize the formulation, the influence of causal factors such as amounts of gelatin, insulin, oleic acid (OA) and the volume ratio of the outer aqueous phase to total and agitation time of the second emulsification process on individual characteristics of the emulsion, such as inner droplet size, viscosity, stability and pharmacological effect, was evaluated first. Based on the analysis of ANOVA, it was concluded that the droplet size of the emulsion was influenced by the volume ratio of the outer aqueous phase significantly. The viscosity of the emulsion was affected by these causal factors and their interactions; however, the most predominant contribution of all causal factors was the volume ratio of the outer aqueous phase. Similarly, one of the most important characteristics in the design of the formulation, stability, was affected by the causal factors. With regard to the hypoglycemic effect, the most influential factor was the content of OA in the emulsion. By means of a novel optimization technique involving a multivariate spline interpolation (MSI), formulation optimization was performed with respect to pharmacological effect and stability, and the optimum formulation with a desirable pharmacological effect and high stability was successfully estimated.