[Development of a One-minute Educational Video for Eye-drop Instillation and Changes in Instillation Behavior after Watching the Video].

We created a one-minute video titled "a simple method of eye-drop instillation" (video) for online instillation guidance, to compare the instillation method before and after study participants watch the video and verify the usefulness of watching the video. Moreover, we prepared a document questionnaire to investigate instillation habits and clarify instillation behavior. Study participants were randomly recruited from among students and faculty members via a poster posted at Tokushima Bunri University. The instillation behavior of the study participants was videotaped before and after they watched the video created by the authors. The images were played in a super slow motion, to confirm success or failure in instillation, drop sites, and eye-opening method. Of the 109 participants in the study, the successful instillation rate before and after watching the video was 55.0% and 69.7%, respectively. The use rate of wet wipes for finger disinfection before instillation increased from 0.0% before watching the video to 74.3% after watching the video. After watching the video, the blinking rate after instillation decreased from 95.4 to 45.0%, the rate of pressing the nasolacrimal duct increased from 2.8 to 77.1%, and the rate of wiping the drug solution spilled around the eyes increased from 89.9 to 98.2%. According to the questionnaire, 72.5% of the participants instilled one drop, 22.0% instilled two drops, and 5.5% instilled three drops or more. Watching the video significantly increased the successful instillation rate and improved instillation behavior. Thus, the video created by the authors can be used for online instillation guidance.

[Formulation Studies and Application of Their Experimental Techniques to Drug Discoveries].

In my first experience as a researcher, I isolated and performed structural predictions of the novel compounds, cis- and trans-palythenic acids, from Noctiluca milialis. I then worked for a pharmaceutical company in a research laboratory of pharmaceutics. I examined an inclusion complex of cinnarizine with ß-cyclodextrin, and found that the inclusion complex did not improve the oral bioavailability of cinnarizine. However, the bioavailability of the inclusion complex after its oral administration was improved by a competing agent. This was the first study to show the potential of a competing agent to improve bioavailability. I subsequently joined a laboratory performing drug discovery research and used experimental techniques from pre-formulation studies. A screening system of solubility for drug design and discovery was constructed to increase the solubilities of compounds synthesized in the laboratory. This screening system contributed to the discovery of a phosphodiesterase type 5 inhibitor with sufficient solubility. As a visiting lecturer at a university, I prepared amoxicillin intragastric buoyant sustained-release tablets for the eradication of Helicobacter pylori and applied cinnarizine as a competing agent. I established a laboratory of pharmaceutics at a university in Tochigi. To develop an enema with fluticasone propionate for ulcerative colitis, I investigated its physicochemical properties and methods to improve its solubility. After moving to another university in Kagawa, I developed a method to reduce the amount of drugs remaining on the surfaces of a pestle and mortar following the grinding of tablets, and new cleaning agents for an automatic dividing packaging machine were discovered.

[Investigation of Successful Eyedrop Instillation Rates and Analysis of Drop Positions Using High-speed Digital Video Recording System].

We investigated the success rates of eyedrop instillation and the distance between the cornea and the dropper tip in 100 volunteers using high-speed digital video recording. Past eyedrop adherence studies assumed that instillation occurred without failure. The ideal distance between the cornea and dropper tip remained unclear, although the general estimate was approximately 2.54 cm (1 inch). This study was approved by the Institutional Review Boards of all participating medical institutions, and all volunteers provided written, informed consent. Successful instillation was defined as when 1 drop fell accurately into the eye on the first attempt. The instillation of ≥2 drops or drops delivered outside the eye was considered a failure. The distance between the eye and dropper tip was measured using still images from a paused digital video camera and a digital ruler. Forty percent of the volunteers instilled eyedrops without instructions from ophthalmologists, pharmacists, or other healthcare workers. When the images were analyzed, the success rate of the first instillation was 70.1%. When the eye was arbitrarily divided into 9 sections, most of the drop sites were the iris or the center of the eye. The distance between the dropper tip and cornea was 2.62±1.75 (median 2.20) cm. These results indicate that the generally recommended distance is usually followed. The successful instillation rate based on the distance from the dropper tip to the cornea was 77% at 1.6±0.88 cm and 54.9% at 4.8±1.25 cm.

A Method for Decreasing the Amount of the Drug Remaining on the Surfaces of the Mortar and Pestle after Grinding Small Amount of Tablets.

The aim of the present study was to develop a method for grinding tablets with a mortar and pestle while reducing drug loss because grinding tablets is known to be associated with reductions in tablet weight and loss of the active drug. Seven kinds of tablets were subjected to grinding. The proportion (%) of the amount of the active drug in the powder remaining on the surfaces of the mortar and pestle relative to the total amount of the drug recovered (the recovery percent) was calculated. The recovery percent of the 7 kinds of tablets ranged from 17.2-35.9%, and the tablets' recovery percent decreased as the tablet weight increased. When the grinding was performed with 1 g of lactose monohydrate or 1 g of D-mannitol moistened with water, the recovery percent of the tablets decreased to 2.6-9.9% and 3.8-9.9%, respectively. The effects of the weight of lactose monohydrate on the recovery percent of Allegra® 60 mg tablets were examined. It was found that at least 0.6 g of lactose monohydrate was required to have a sufficient effect on drug recovery. Therefore, additives that have stronger effects at lower amounts were sought. As a result, calcium monohydrogen phosphate was found to have the strongest effect on drug recovery. The addition of 0.4 g calcium monohydrogen phosphate resulted in the recovery percent of 5.1%, which was significantly lower than that of 15.0% observed after the addition of 0.4 g lactose monohydrate, and lower than the 6.8% of 1 g lactose monohydrate.

Degradation rates and products of fluticasone propionate in alkaline solutions.

The apparent degradation rate constant of fluticasone propionate (FLT) in 0.1 M NaOH:methanol=1:1 at 37 °C was previously reported to be 0.169±0.003 h-1, and four degradation products (products 1-4) were observed in the solution. The aims of the present study were to assess the degradation rates of FLT in other alkaline solutions and clarify the chemical structures of the four degradation products in order to obtain basic data for designing an enema for inflammatory bowel disease. The apparent degradation rate constants in 0.05 M NaOH and 0.1 M NaOH:CH3CN=1:1 were 0.472±0.013 h-1 and 0.154±0.000 h-1 (n=3), respectively. The chemical structures of products 1-4 in 0.1 M NaOH:methanol=1:1 were revealed by nuclear magnetic resonance (NMR) and mass spectrometry data. The chemical structure of products 2 was that the 17-position of the thioester moiety of FLT was substituted by a carboxylic acid. The degradation product in 0.1 M NaOH:CH3CN=1:1 was found to be product 2 based on 1H NMR data. The degradation product in 0.05 M NaOH was considered to be product 2 based on the retention time of HPLC. These results are useful for detecting the degradation products of FLT by enzymes of the intestinal bacterial flora in the large intestine after dosing FLT as an enema.

Degradation rates and products of fluticasone propionate in alkaline solutions / 药物分析学报

The apparent degradation rate constant of fluticasone propionate (FLT) in 0.1 M NaOH:methanol=1:1 at 37 ℃ was previously reported to be 0.169 ± 0.003 h?1, and four degradation products (products 1–4) were observed in the solution. The aims of the present study were to assess the degradation rates of FLT in other alkaline solutions and clarify the chemical structures of the four degradation products in order to obtain basic data for designing an enema for inflammatory bowel disease. The apparent degradation rate constants in 0.05 M NaOH and 0.1 M NaOH:CH3CN=1:1 were 0.472 ± 0.013 h?1 and 0.154 ± 0.000 h?1 (n=3), respectively. The chemical structures of products 1–4 in 0.1 M NaOH:methanol=1:1 were revealed by nuclear magnetic resonance (NMR) and mass spectrometry data. The chemical structure of products 2 was that the 17-position of the thioester moiety of FLT was substituted by a carboxylic acid. The degradation product in 0.1 M NaOH:CH3CN=1:1 was found to be product 2 based on 1H NMR data. The degradation product in 0.05 M NaOH was considered to be product 2 based on the retention time of HPLC. These results are useful for detecting the degradation products of FLT by enzymes of the intestinal bacterial flora in the large intestine after dosing FLT as an enema.

Degradation rates and products of fluticasone propionate in alkaline solutions / 药物分析学报

The apparent degradation rate constant of fluticasone propionate (FLT) in 0.1 M NaOH:methanol=1:1 at 37 ℃ was previously reported to be 0.169 ± 0.003 h?1, and four degradation products (products 1–4) were observed in the solution. The aims of the present study were to assess the degradation rates of FLT in other alkaline solutions and clarify the chemical structures of the four degradation products in order to obtain basic data for designing an enema for inflammatory bowel disease. The apparent degradation rate constants in 0.05 M NaOH and 0.1 M NaOH:CH3CN=1:1 were 0.472 ± 0.013 h?1 and 0.154 ± 0.000 h?1 (n=3), respectively. The chemical structures of products 1–4 in 0.1 M NaOH:methanol=1:1 were revealed by nuclear magnetic resonance (NMR) and mass spectrometry data. The chemical structure of products 2 was that the 17-position of the thioester moiety of FLT was substituted by a carboxylic acid. The degradation product in 0.1 M NaOH:CH3CN=1:1 was found to be product 2 based on 1H NMR data. The degradation product in 0.05 M NaOH was considered to be product 2 based on the retention time of HPLC. These results are useful for detecting the degradation products of FLT by enzymes of the intestinal bacterial flora in the large intestine after dosing FLT as an enema.

Determination of metronidazole in a rat stomach by HPLC for obtaining basic data of the eradication therapy of Helicobacter pylori.

In the eradication therapy of Helicobacter pylori changes of antibiotics as these concentrations or amount in the stomach after oral administration were not clear. A simple and accurate method for determining the concentration of metronidazole (MTZ) in homogenate of rat stomach was developed in order to obtain basic data to design a pharmaceutical preparation having targeting ability to the surface of gastric-mucosa. This method included a deproteinization process by methanol, separation with reversed-phase high-performance liquid chromatography, and detection with an ultraviolet wavelength of 370 nm. Regression analysis showed that the method was linear over a standard curve range from 5 µg/mL to 2000 µg/mL. The inter-day precision and accuracy values between the ranges were 5.0% or better and -7.5 to 5.2%, respectively. The newly developed method was applied to an analysis of gastric samples after oral administration of MTZ at a dose of 5 mg/kg. It was found that the residual MTZ in the stomach was determined within 5 h after dosing. This method is useful for monitoring MTZ in stomach after its oral administration to rats.

Effect of beta-cyclodextrin on the degradation rate of amoxicillin in acidic solution.

The formation of an inclusion complex of amoxicillin (AMX) with beta-cyclodextrin (beta-CD) in aqueous solution was confirmed by a solubility method and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The apparent stability constant for the inclusion complex was 10.72 M(-1) in water at 25 degrees C. The effect of alpha-CD, beta-CD, and gamma-CD on the degradation of AMX in a pH 1.2 solution at 37 degrees C was investigated. beta-CD and gamma-CD reduced the rate of degradation. alpha-CD had no effect. These results were consistent with those of 1H-NMR spectroscopy. The effect of beta-CD on the degradation rate was studied in more detail. The apparent first order rate constant for the degradation of AMX in the pH 1.2 solution at 37 degrees C was 0.1121 h(-1) (t(1/2)=6.18 h), which decreased with the addition of beta-CD. The rate constants and t(1/2) values for the concentrations of beta-CD added, corresponding to molar ratios of AMX to beta-CD of 1:0.5, 1:1, 1:2, 1:5, and 1:10, were 0.1051 h(-1) and 6.59 h, 0.0992 h(-1) and 6.98 h, 0.0893 h(-1) and 7.76 h, 0.0697 h(-1) and 9.95 h, and 0.0509 h(-1) and 13.61 h, respectively. The activation energy for the degradation of AMX in the pH 1.2 solution was increased from 6.9 x 10(4) J/mol (AMX alone) to 8.0 x 10(4) J/mol (AMX:beta-CD=1:10).

Are the optimum pharmaceutical preparations used for the second-line eradication therapy for helicobacter pylori infection in Japan? - a discussion from a simulation for the amount of antibiotics in stomach based on the data of dissolution studies -.

The purpose of this study was to evaluate whether the optimum preparations are used for the second-line eradication therapy for Helicobacter pylori (H. pylori) infection in Japan. In the therapy, commercial tablets, which have 250 mg of amoxicillin (AMX) and 250 mg of metronidazole (MTZ), are used as antibiotics. The evaluation was performed by dissolution tests and simulations for intragastric drug concentrations based on the dissolution data. The dissolution tests were performed using the paddle method of Japanese pharmacopoeia XV. The data obtained were used for the simulation of intragastric drug concentrations. In dissolution studies, the 100% dissolution time (T100%) of AMX from the tablet which was about 20 min was faster than that from AMX alone (about 6 h). T100% of MTZ from the tablet which was about 3 h was later than that from MTZ alone (about 30 min). In simulated intragastric concentrations, the time above minimum inhibitory concentration (MIC) of the AMX tablet was 6.6 h which was shorter than that of AMX (11.4 h). The Cmax of the MTZ tablet was 0.095 mg/ml which was lower than that of MTZ (0.190 mg/ml). However, AMX is a timedependent antibiotic, longer duration above MIC is desirable. On the other hand, MTZ is a concentration-dependent antibiotic, higher Cmax is desirable. In conclusion, the commercial products are found to be not the best, and preparing an AMX pharmaceutical preparation with more sustained release characteristic and a MTZ preparation with more rapid release characteristic are considered to be very advantageous.

Improvement of oral bioavailability of flurbiprofen from flurbiprofen/beta-cyclodextrin inclusion complex by action of cinnarizine.

Improvement of the oral bioavailability of flurbiprofen (Flu) after oral administration of flurbiprofen/beta-cyclodextrin inclusion complex (Flu/beta-CD) by the action of cinnarizine (CN) was investigated. Flu and Flu/beta-CD were administered orally to fasted rats at a dose of 20mg/kg as Flu. Thirty minutes after drug administration, CN dissolved in pH 4.0 buffer solution or pH 4.0 buffer solution alone was administered to the rats. The dose of CN was 0.17 mg/kg. Blood samples were taken from rats and Flu concentrations in plasma samples were determined by HPLC. It was found from the comparison of Flu and Flu with CN (Flu+CN) that CN had no effect on plasma concentrations of Flu after oral administration of Flu. The mean plasma levels after oral administration of Flu/beta-CD with CN (Flu/beta-CD+CN) were larger not only than those of Flu and Flu+CN but also than those of Flu/beta-CD. The value of C(max) in Flu/beta-CD+CN was significantly larger than that of Flu/beta-CD. This is considered to be caused by the action of CN as a competing agent. This mechanism was supported by the result of solubility study in which Flu solubility in beta-CD solution decreased with the addition of CN. It was found from these results that CN had strong ability as a competing agent in vivo.

[In-vitro evaluation of cinnarizine as a competing agent to beta-cyclodextrin inclusion complexes: effect of cinnarizine on the membrane permeation rate of progesterone from its beta-cyclodextrin inclusion complex].

The use of competing agents is considered a powerful tool for the development of a drug-delivery system with drug/cyclodextrin inclusion complexes. However, there are very few studies examining this issue. To explain this phenomenon, it was thought that a competing agent with a sufficiently high stability constant had not yet been reported. In this study, cinnarizine (CN), which has a high stability constant with beta-cyclodextrin (beta-CD) and unique solubility characteristics, was selected, and its ability as a competing agent was examined in a membrane permeability study. The permeability study showed that the permeation rates of the drugs flurbiprofen, progesterone, and spironolactone decreased with their stability constants with the addition of beta-CD. In one of the drugs, progesterone (Pro), the decrease was restored by the addition of CN. The amount of CN added was a 1:1 molar ratio to the amount of Pro. However, no similar action was induced with the addition of DL-phenylalanine (Phe) in the permeation study at the 1:5 (Pro:Phe) molar ratio. These finding indicate that CN acts as a competing agent, and its action is much stronger than that of Phe.

Preparation of amoxicillin intragastric buoyant sustained-release tablets and the dissolution characteristics.

An intragastric buoyant sustained-release tablet (IGB-T) containing 100 mg of amoxicillin (AMX) was prepared to eradicate gastric Helicobacter pylori. A tablet prepared by compressing the mixture of hydroxypropylcellulose-H (HPC-H), citric acid (17.2 mg), sodium hydrogen carbonate (22.8 mg) and AMX was employed as the basic system for preparing IGB-T. The weight and diameter of the tablets were designed to be about 300 mg and 10 mm, respectively. IGB-T containing 5 mg of AMX and HPC-H (255 mg) was buoyant and showed a sustained-release pattern in water. However, when AMX was increased and HPC-H decreased to maintain the tablet weight (300 mg), there was no apparent sustained-release pattern. To prepare IGB-T containing 50 mg of AMX, the surface of the tablet was coated with HPC-H after a tablet was prepared from the mixture of AMX (50 mg), HPC-H (210 mg), citric acid (17.2 mg), and sodium hydrogen carbonate (22.8 mg). This tablet (IGB-T50-Coating) was buoyant and showed a sustained-release pattern in water. However, to complete IGB-T with 100 mg of AMX, it was necessary not only to coat the surface of the tablet but also to use granulated AMX with a particle size of 300-500 microm (IGB-T100-Coating-300-500G). IGB-T100-Coating-300-500G was confirmed to be buoyant for 24 h while maintaining a tablet shape and showed a sustained-release pattern in water and buffer solutions of pH 1.2 and 6.8.

Stability of spironolactone in rat plasma: strict temperature control of blood and plasma samples is required in rat pharmacokinetic studies.

The stability of spironolactone (SPN) in rat plasma was studied and its degradation was found to be an apparent first-order reaction. The apparent first-order rate constants (k(obs)) at 37, 23.5 and 0 degrees C were 3.543+/-0.261 (h-1, mean+/-S.D., n=3), 6.278+/-0.045 (x10(-1) h-1), and 7.336+/-0.843 (x10(-2) h-1), respectively. The half-lives were 0.20 h, 1.10 h, and 9.53 h. The degradation rate of SPN in rat plasma was markedly decreased when NaF, an esterase inhibitor, was added to the plasma, and the degradation was catalyzed by esterase in the plasma. These results indicated that not only plasma but also blood and serum samples in rat pharmacokinetic studies should be cooled to 0 degrees C, the temperature maintained, and treated as soon as possible. In pharmacokinetic studies reported previously, the temperature control of plasma, blood, and serum samples was not described. The pharmacokinetic study in rats after intravenous administration of SPN at 20 mg/kg was performed with strict temperature control of plasma and blood samples. The AUC, MRT, CL and Vd(ss) values (mean+/-S.E. of 4 rats) for SPN were 4100.8+/-212.9 ng h/ml, 0.29+/-0.01 h, 4915.7+/-248.0 ml/h/kg, and 1435.4+/-48.4 ml/kg, respectively. The AUC value was much larger than that previously reported. The AUC, MRT, Cmax and Tmax values (mean+/-S.E. of 4 rats) of canrenone, an active metabolite of SPN, after the administration of SPN were 4196.1+/-787.5 ng h/ml, 1.99+/-0.13 h, 1546.3+/-436.4 ng/ml and 1.0+/-0.0 h, respectively. This AUC value was almost identical to the value previously reported.

Evaluation of the bioavailability of flurbiprofen and its beta-cyclodextrin inclusion complex in four different doses upon oral administration to rats.

The dissolution profiles of flurbiprofen (Flu) and its beta-cyclodextrin inclusion complex (Flu/beta-CD) in buffer solutions at various pH values were examined. The percent dissolved at 15 min for Flu and Flu/beta-CD was almost 100% at pH 6.8 and 8.0 but the dissolution rate of Flu was extremely reduced at pH 1.2 and 4.0. In these lower pH conditions, Flu/beta-CD improved the dissolution rate of Flu. The percent dissolved at 1 h for Flu/beta-CD at pH 1.2 and 4.0 were 33.4 and 41.3%, respectively, and about 10 times larger than those for Flu. The oral bioavailability of Flu from Flu or Flu/beta-CD at doses of 1, 3, 10, and 30 mg/kg (as Flu) was examined in rats. An apparent linear relationship between doses and C(max) and AUC was observed after administration of Flu and Flu/beta-CD. The Flu C(max) and AUC values at 30 mg/kg, however, were much lower than would have been predicted from doses of 1-10 mg/kg. Those of Flu/beta-CD were also lower than the predicted values, but the gap was quite small. The results suggest that the absorption of Flu in rats was saturated at 10 mg/kg, and that the enhanced dissolution rate of Flu/beta-CD increased the saturation dose to 30 mg/kg.