Real-Time Quantitative Evaluation of a Drug during Liposome Preparation Using a Probe-Type Raman Spectrometer.

During the manufacturing process of liposome formulations, it is considered difficult to evaluate their physicochemical properties and biological profiles due to the complexity of their structure and manufacturing process. Conventional quality evaluation is labor-intensive and time-consuming; therefore, there was a need to introduce a method that could perform in-line, real-time evaluation during the manufacturing process. In this study, Raman spectroscopy was used to monitor in real time the encapsulation of drugs into liposomes and the drug release, which are particularly important quality evaluation items. Furthermore, Raman spectroscopy combined with partial least-squares (PLS) analysis was used for quantitative drug evaluation to assess consistency with results from UV-visible spectrophotometry (UV), a common quantification method. The prepared various ciprofloxacin (CPFX) liposomes were placed in cellulose tubes, and a probe-type Raman spectrophotometer was used to monitor drug encapsulation, the removal of unencapsulated drug, and drug release characteristics in real time using a dialysis method. In the Raman spectra of the liposomes prepared by remote loading, the intensities of the CPFX-derived peaks increased upon drug encapsulation and showed a slight decrease upon removal of the unencapsulated drug. Furthermore, the peak intensity decreased more gradually during the drug release. In all Raman monitoring experiments, the discrepancy between quantified values of CPFX concentration in liposomes, as measured by Raman spectroscopy combined with partial least-squares (PLS) analysis, and those obtained through ultraviolet (UV) spectrophotometry was within 6.7%. The results revealed that the quantitative evaluation of drugs using a combination of Raman spectroscopy and PLS analysis was as accurate as the evaluation using UV spectrophotometry, which was used for comparison. These results indicate the promising potential of Raman spectroscopy as an innovative method for the quality evaluation of liposomal formulations.

Exploring Novel Cocrystalline Forms of Oxyresveratrol to Enhance Aqueous Solubility and Permeability across a Cell Monolayer.

Oxyresveratrol (ORV) is a naturally extracted compound with many pharmacological activities. However, information about the crystalline form is not known when considering the development of a form for oral dosage. Cocrystal engineering offers drug molecular understanding and drug solubility improvements. Thus, we attempted cocrystallization of ORV using 10 carboxylic acids as a coformer at a 1:1 M ratio. Each combination was processed with liquid-assisted grinding, solvent evaporation and a slurry method, then characterized by powder X-ray powder diffraction (PXRD), conventional and low-frequency Raman spectroscopy and thermal analysis. The solubility, dissolution and permeation studies across Caco-2 cell monolayers were conducted to evaluate the ORV samples. A screening study revealed that an ORV and citric acid (CTA) cocrystal formed by ethyl acetate-assisted grinding had characteristic PXRD peaks (14.0 and 16.5°) compared to those of ORV dihydrate used as a starting material. Low-frequency Raman measurements, with peaks at 100 cm-1, distinguished potential cocrystals among three processing methods while conventional Raman could not. An endothermic melt (142.2°C) confirmed the formation of the novel crystalline complex. The solubility of the cocrystal in the dissolution media of pH 1.2 and 6.8 was approximately 1000 µg/mL, a 1.3-fold increase compared to ORV alone. In vitro cytotoxicity studies showed that the cocrystal and physical blend were not toxic at concentrations of 25 and 12.5 µM ORV, respectively. The ORV-CTA cocrystal enhanced the cellular transport of ORV across Caco-2 monolayers. Therefore, cocrystallization could be used to improve aqueous solubility and permeability, leading to better oral bioavailability of ORV.

Prediction model of compensation for contralateral kidney after living-donor donation.

BACKGROUND: Compensation of contralateral kidney function after living-donor kidney donation is well known, and many predictive factors have been proposed. However, no prediction model has been proposed. This study was performed to establish a tool with which to estimate the degree of compensation of the contralateral kidney after living-donor kidney donation. METHODS: We retrospectively analyzed 133 living donors for renal transplantation in our institution. We defined a favorable compensation as a post-donation estimated glomerular filtration rate (eGFR) at 1 year (calculated by the Chronic Kidney Disease Epidemiology Collaboration equation) of > 60% of the pre-donation eGFR. We analyzed the living donors' clinical characteristics and outcomes. RESULTS: The median (range) donor age was 59 (24-79) years, median (range) body mass index was 22.9 (16.8-32.7) kg/m2, and median (range) body surface area was 1.6 (1.3-2.0) m2. All donors were Japanese, and 73% of the donors were biologically related. The median (range) donor pre-donation eGFR was 108.7 (82-144) ml/min/1.73 m2, and the median (range) post-donation eGFR at 1 year was 86.9 (43-143) ml/min/1.73 m2. Eighty-six percent of donors had compensatory hypertrophy. In the univariate analysis, age, female sex, history of hypertension, body surface area, and pre-donation eGFR were significantly associated with hypertrophy (p < 0.05). In the multivariate analysis, age, female sex, history of hypertension, and ratio of the remnant kidney volume to body weight were significantly associated with hypertrophy (p < 0.05). Based on these results, we created a compensation prediction score (CPS). The median (range) CPS was 8.7 (1.1-17.4). Receiver operating characteristic analysis showed strong diagnostic accuracy for predicting favorable compensation (area under the curve, 0.958; 95% confidence interval, 0.925-0.991, p < 0.001). The optimal cut-off value of the CPS was 5.0 (sensitivity, 92.0%; specificity, 89.5%). The CPS had a strong positive correlation with the post-donation eGFR (R = 0.797, p < 0.001). CONCLUSION: The CPS might be useful tool with which to predict a favorable compensation of the contralateral kidney and remnant kidney function. If the CPS is low, careful management and follow-up might be necessary. Further investigations are needed to validate these findings in larger populations.

Measurement of the Water Content in Semi-solid Formulations Used to Treat Pressure Ulcers and Evaluation of Their Water Absorption Characteristics.

We investigated the water contents in commercial semi-solid preparations used for pressure ulcer (PU) treatment using near-IR spectroscopy (NIRS) and compared the results with those measured using the Karl Fischer (KF) method. The aim of this study was to determine a standard method and select the appropriate topical preparation with the optimal moisture for PU treatment. The water absorption properties of bases and formulations were evaluated with a time-dependent factor using Transwell as the model membrane. KF and NIRS were applicable as measurement methods of the water content in semi-solid formulations. NIRS was shown to be a useful, simple, nondestructive tool that is more advantageous than the KF method. The water absorption characteristics tested using Transwell revealed that the rate of and capacity for water absorption are determined not only by the absorption ability of the polymer base but also by other factors, such as the osmotic pressure exerted by additives. KF and NIR measurements can be used to choose external skin preparations to control the amount of water in PU treatment.

Molecular State of Active Pharmaceutical Ingredients in Ketoprofen Dermal Patches Characterized by Pharmaceutical Evaluation.

The molecular states of ketoprofen and the interaction between ketoprofen and other pharmaceutical excipients in the matrix layer were examined to determine their effect on the pharmaceutical properties of original and generic ketoprofen dermal patches (generic patches A and B). Molecular states of ketoprofen were evaluated using polarized light microscopy, Raman spectroscopy and powder X-ray diffraction. For the original ketoprofen patch, crystalline components were not observed in the matrix layer. However, crystalline ketoprofen was observed in the two generic ketoprofen patches. Moreover, the ketoprofen exhibited hydrogen bonding with the pharmaceutical excipients or patch materials in the generic products. Skin permeation of ketoprofen from the patches was evaluated using hairless mouse skin. Twelve hours after application, the original patch demonstrated the highest level of cumulative skin permeation of ketoprofen. This was followed by generic patch B while generic patch A showed the lowest level of permeation. Fluxes were calculated from the skin permeation profiles. The original patch was approx. 2.4-times faster compared with generic patch A and approximately 1.9-times faster compared with generic patch B. This investigation suggested that pharmaceutical properties such as skin permeability for these types of products are affected by the precipitation of crystalline ketoprofen in the matrix layer and the interaction of ketoprofen with the pharmaceutical excipients or patch materials.

Biocompatible topical delivery system of high-molecular-weight hyaluronan into human stratum corneum using magnesium chloride.

Non-invasive delivery of hyaluronan into the stratum corneum (SC) is extremely difficult because of its high molecular weight and the strong barrier of the SC. We developed a safe method of administering hyaluronan into the human SC and determined its penetration route. The amount of hyaluronan that penetrated into the SC was 1.5-3 times higher in the presence of magnesium chloride hexahydrate (MgCl2) than other metal chlorides. The root-mean-square radius of hyaluronan in water decreased with the addition of MgCl2. Moreover, MgCl2 solutions maintained their dissolved state on a plastic plate for a long time, suggesting that size compaction and inhibition of hyaluronan precipitation on the skin enhanced hyaluronan into the SC. Our results also strongly suggest that an intercellular route contributes to the penetration of hyaluronan from the upper to the middle layer of the SC. No disruption to the SC barrier was observed after continuous use once a day for 1 month, demonstrating the potential of our method for the safe, topical application of hyaluronan.

Validity and reliability of Psychiatric Nurse Self-Efficacy Scales: cross-sectional study.

OBJECTIVES: To develop the Psychiatric Nurse Self-Efficacy Scales, and to examine their reliability and validity. DESIGN: We developed the Improved Self-Efficacy Scale (ISES) and Decreased Self-Efficacy Scale (DSES) using existing evidence. Statistical analysis was conducted on the data to test reliability and validity. SETTING: The study's setting was psychiatric facilities in three prefectures in Japan. PARTICIPANTS: Data from 514 valid responses were extracted of the 786 responses by psychiatric nurses. OUTCOME MEASURES: The study measured the reliability and validity of the scales. RESULTS: The ISES has two factors ('Positive changes in the patient' and 'Prospect of continuing in psychiatric nursing') and the DSES has three ('Devaluation of own role as a psychiatric nurse', 'Decrease in nursing ability due to overload' and 'Difficulty in seeing any results in psychiatric nursing'). With regard to scale reliability, the Cronbach's alpha coefficient was 0.634-0.845. With regard to scale validity, as the factorial validity of the ISES and DSES, for the ISES, χ2/df (110.625/37) ratio=2.990 (p<0.001), goodness-of-fit index (GFI)=0.962, adjusted GFI (AGFI)=0.932, comparative fit index (CFI)=0.967 and root mean square error of approximation (RMSEA)=0.062; for the DSES, χ2/df (101.982/37) ratio=2.756 (p<0.001), GFI=0.966, AGFI=0.940, CFI=0.943, RMSEA=0.059 and Akaike Information Criterion=159.982. The concurrent validity of the General Self-Efficacy Scale was r=0.149-0.446 (p<0.01) for ISES and r=-0.154 to -0.462 (p<0.01) for DSES, and the concurrent validity of the Stress Reaction Scale was r=-0.128 to 0.168 for ISES, r=0.214-0.398 for DSES (p<0.01).Statistical analyses showed the scales to be reliable and valid measures. CONCLUSIONS: The ISES and DSES can accurately assess psychiatric nurses' self-efficacy. Using these scales, it is possible to formulate programmes for improving psychiatric nurses' feelings of self-efficacy.

Potential application of novel liquid crystal nanoparticles of isostearyl glyceryl ether for transdermal delivery of 4-biphenyl acetic acid.

Novel liquid crystal nanoparticles (LCNs) composed of isostearyl glyceryl ether (GE-IS) and ethoxylated hydrogenated castor oil (HCO-60) were developed for the enhanced transdermal delivery of 4-biphenyl acetic acid (BAA). The physical properties and pharmaceutical properties of the LCNs were measured. The interaction between the intercellular lipid model of the stratum corneum and the LCNs was observed to elucidate the skin permeation mechanism. In the formulation, the LCNs form niosomes with mean particles sizes of 180-300 nm. The skin absorption mechanisms of LCNs are different, depending upon the application and buffer concentration. The LCNs composed of GE-IS and HCO-60 are attractive tools for use as transdermal drug delivery systems carriers for medicines and cosmetics, due to their high efficiency and safety.

[Pharmaceutical Properties of Anti-inflammatory Analgesic Patches Using Acrylic Polymer].

The mock patches were prepared with novel acrylic polymers as adhesive layer where biphenyl-4-ylacetic acid (BAA) or 2-(2-fluorobiphenyl-4-yl) propanoic acid (FPA) was used as model active pharmaceutical ingredients (APIs). In addition, the mock patches were formulated with typical ester ingredients for transdermal dosage forms. The molecular state of the model APIs in the adhesive layer was observed by polarized microscope and microscopic Raman spectroscopy, which contains both conventional and low frequency (LF) region. Crystallization behavior would be depended on the interaction between API and polymers in the adhesive layer. In particular, LF Raman measurement was useful to discriminate API polymorphs. The pharmaceutical properties including dissolution and skin permeation of APIs were also evaluated for mock patches. The drug release and transdermal permeation were enhanced with the ester ingredients such as isopropyl myristate and diethyl sebacate due to their diffusion to the test solution or the skin stratum corneum as well as reducing the interaction between API and polymers. Further, the tack strength was not changed, but the peel strength was weakened by the additives. Thus, the adhesive properties were controllable by formulation with the additives. These findings could enable to evaluate the interaction between API and the polymers for adhesive layer and select the appropriate polymer and additives for used APIs when designing the drug products.

Optimizing Intraoperative Blood Pressure to Improve Outcomes in Living Donor Renal Transplantation.

BACKGROUND: Adequate renal perfusion at the time of unclamping is important because it has been known to affect outcomes in renal transplantation. Nevertheless, the ideal intraoperative systolic arterial pressure (SAP) has not been well defined. METHODS: We performed a retrospective analysis of 106 living donor renal transplants performed at our center from June 2010 to May 2019. We divided the cohort into 2 groups according to our center's goal SAP of ≥150 mm Hg: 57 patients had SAP ≥150 mm Hg and 49 patients had SAP <150 mm Hg. We analyzed pretransplant characteristics, intraoperative measurements, and postoperative laboratory values to validate our center's target SAP at the time of reperfusion. This study strictly complied with the Helsinki Congress and the Istanbul Declaration regarding donor sources. RESULTS: Patients with SAP ≥150 mm Hg had been on dialysis for a significantly shorter duration before transplant compared with those who had SAP <150 mm Hg. In the SAP ≥150 mm Hg group, urinary sodium excretion normalized earlier, and they had a significantly smaller stroke volume variation, higher cardiac output and cardiac index, earlier initial urination, and higher intraoperative urine output. There were no differences in intraoperative volume repletion, central venous pressure, or postoperative estimated glomerular filtration rate. CONCLUSION: Achieving SAP ≥150 mm Hg at the time of reperfusion may be associated with early stabilization of graft function. Nevertheless, our data suggested that recipients with a prolonged dialysis history are less likely to achieve SAP ≥150 mm Hg at the time of unclamping in living donor renal transplantation.

Is the Living Donor Kidney Profile Index Valuable in Japanese Patients?

INTRODUCTION: The Living Kidney Donor Profile Index (LKDPI) was recently proposed in the United States to evaluate living donor quality. Japan has a largely different renal transplant circumstance, such as a high ABO incompatibility rate. The aim of this study was to validate the LKDPI among the Japanese population and adjust the score. METHODS: We performed a retrospective analysis of 133 living donors in renal transplant in our institution. We analyzed the clinical characteristics and outcomes, and created a modified LKDPI score considering the favorable ABO incompatible kidney transplant outcomes in Japan. RESULTS: Median (interquartile range [IQR]) donor age was 59 (51 to 65) and median (IQR) body mass index was 22.9 kg/m2 (20.9 to 25.2). ABO incompatibility rate was 28.5%. Median (IQR) donor estimated glomerular filtration rate (eGFR) (Chronic Kidney Disease Epidemiology Collaboration equation) was 108.7 mL/min/1.73 m2 (99.9 to 115.5). The 1-year graft survival rate was 98.5%, and the 3-year graft survival rate was 97%. The incidence of antibody mediated rejection was 5.2%. The median (IQR) LKDPI score was 30.2 (11.8 to 46.8). This was significantly higher than the previously reported score in the United States, which was 12.8 (-0.8 to 27.2). The modified LKDPI (mLKDPI) score was 23.2 (4.1 to 35.1). LKDPI and mLKDPI did not show a diagnostic value in graft survival; however, LKDPI and mLKDPI showed significant diagnostic value in eGFR at 1 year (area under the curve [AUC]=0.627, P = .017; and AUC=0.673, P = .01). CONCLUSION: Our outcomes had better survival even though with higher ABO incompatibility rate. According to original LKDPI, our donor pool is higher than the general US population. In this study, lower LKDPI tended to be associated with good allograft function, and mLKDPI has better diagnostic value than LKDPI. To compare internationally, an adjusted model for Japan might be necessary based on the outcomes of a large population.

Impact of Very Low-Dose Trimethoprim-Sulfamethoxazole on Serum Creatinine after Renal Transplantation: A Retrospective Study.

BACKGROUND: It is well known that high-dose trimethoprim, through its effect of inhibiting creatinine secretion, increases serum creatinine levels without changes in real glomerular filtration rate. However, there has been no report regarding the effect of very low-dose trimethoprim on serum creatinine levels after renal transplantation. METHODS: We retrospectively investigated 76 renal transplantation recipient outpatients who completed their course of initial prophylaxis at our institution. Twelve patients who experienced events that might affect their serum creatinine levels were excluded. Fifty-one patients who required readministration of trimethoprim-sulfamethoxazole to prevent a possible outbreak of pneumocystis jirovecii pneumonia and 13 patients who did not receive readministration (control) were analyzed. Dosage was 80 mg/400 mg (per tablet), administered as 3 tablets per week for 30.6 ± 13.5 days. This study strictly complied with the Helsinki Congress and the Istanbul. Declaration regarding donor source. RESULTS: All patients completed readministration without adverse events. Serum creatinine increased significantly in the readministration group (1.40 ± 0.64 mg/dL to 1.48 ± 0.70 mg/dL, P < .01) while not in the control group. The higher the initial serum creatinine level, the greater the increase of Δ serum creatinine (R = 0.59, P < .001). Sex, baseline urine protein level, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use, donor type, and time after renal transplantation did not affect Δ serum creatinine. Serum creatinine returned to baseline levels after cessation. CONCLUSIONS: Very low-dose trimethoprim-sulfamethoxazole prophylaxis significantly raised serum creatinine reversibly by 6% after renal transplantation.

Imaging Analysis Enables Differentiation of the Distribution of Pharmaceutical Ingredients in Tacrolimus Ointments.

We demonstrated the difference in the distribution state of pharmaceutical ingredients between tacrolimus (TCR) original ointment and six kinds of generic medicines. Two-dimensional imaging and depth analysis using attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy and confocal Raman microscopy were used, in addition to the evaluation of pharmaceutical properties, including spreading properties, rheological properties, and amount of solvent. The solvents, such as propylene carbonate and triacetin, in TCR ointments formed liquid droplets and dispersed in hydrocarbon oils. Waxes, white beeswax and beeswax, formed other domains. Confocal Raman microscopy could detect liquid droplet size without coalescence of that on germanium or glass surfaces. The combination of ATR FT-IR and confocal Raman imaging would be a powerful tool to reveal the size and shape of liquid droplets of pharmaceutical ingredients in semisolid formulations.

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.

Biradical character of linear π-conjugated oligomer dications composed of thiophene, pyrrole, and methylthio end-capping units.

Combined DFT calculations and UV-vis-NIR, ESR, and SQUID measurements revealed that the ground-state electronic structure of a linear π-conjugated oligomer dication composed of two pyrrole and six or seven thiophene rings and methylthio end-capping units is dominated by a singlet biradical character.