Lyotropic liquid crystal-based transcutaneous peptide delivery system: Evaluation of skin permeability and potential for transcutaneous vaccination

Transcutaneous drug delivery is a promising method in terms of drug repositioning and reformulation because of its non-invasive and easy-to-use features. To overcome the skin barrier, which is the biggest challenge in transcutaneous drug delivery, a number of techniques, such as microemulsion, solid-in-oil dispersions and liposomes, have been studied extensively. However, the low viscosity of these formulations limits drug retention on the skin and reduces patient acceptability. Although viscosity can be increased by adding a thickening reagent, such an addition often alters formulation nanostructures and drug solubility, and importantly, decreases skin permeability. In this study, a gel-like lyotropic liquid crystal (LLC) was used as a tool to enhance skin permeability. In particular, we prepared 1-monolinolein (ML)-based LLCs with different water contents. All LLCs significantly enhanced skin permeation of a peptide drug, an epitope peptide of melanoma, despite their high viscoelasticity. Fourier transform infra-red spectroscopic analysis of the skin surface treated with the LLCs revealed that the gyroid geometry more strongly interacted with the lamellar structure inside the stratum corneum (SC) than the diamond geometry. Finally, as the result of the in vivo tumor challenge experiment using B16F10 melanoma-bearing mice, the LLC with the gyroid geometry showed stronger vaccine effect against tumor than a subcutaneous injection. Collectively, ML-based LLCs, especially with the gyroid geometry, are a promising strategy to deliver biomacromolecules into skin. STATEMENT OF SIGNIFICANCE: Transcutaneous drug delivery is a promising method for drug repositioning and reformulation because of its non-invasive and easy-to-use features. To overcome the skin barrier, which is the biggest challenge in transcutaneous drug delivery, we used a gel-like lyotropic liquid crystal (LLC) as a novel tool to enhance skin permeability. In this paper, we demonstrated that an LLC with a specific liquid crystalline structure has the highest skin permeation enhancement effect for a peptide antigen as a model drug. Moreover, the peptide antigen-loaded LLC showed a vaccine effect that was comparable to a subcutaneous injection in vivo. This study provides a basis for designing a transcutaneous delivery system of peptide drugs with LLC.

Accuracy of self-reported height, weight and waist circumference in a Japanese sample

Objective

Inconsistent results have been found in prior studies investigating the accuracy of self‐reported waist circumference, and no study has investigated the validity of self‐reported waist circumference among Japanese individuals. This study used the diagnostic standard of metabolic syndrome to assess the accuracy of individual's self‐reported height, weight and waist circumference in a Japanese sample.

Methods

Study participants included 7,443 Japanese men and women aged 35–79 years. They participated in a cohort study's baseline survey between 2007 and 2011. Participants' height, weight and waist circumference were measured, and their body mass index was calculated. Self‐reported values were collected through a questionnaire before the examination.

Results

Strong correlations between measured and self‐reported values for height, weight and body mass index were detected. The correlation was lowest for waist circumference (men, 0.87; women, 0.73). Men significantly overestimated their waist circumference (mean difference, 0.8 cm), whereas women significantly underestimated theirs (mean difference, 5.1 cm). The sensitivity of self‐reported waist circumference using the cut‐off value of metabolic syndrome was 0.83 for men and 0.57 for women.

Conclusions

Due to systematic and random errors, the accuracy of self‐reported waist circumference was low. Therefore, waist circumference should be measured without relying on self‐reported values, particularly in the case of women.

Successful double autografts for patients with relapsed clear cell sarcoma of the kidney

Although the prognosis of clear cell sarcoma of the kidney (CCSK) has improved, when metastases occur the probability of cure is very low. We have treated two pediatric patients with relapsed CCSK, one with multiple bone metastases and another with brain metastases. After one or two courses of re-induction chemotherapy and radiation therapy to the sites of metastasis, they received double high-dose chemotherapy with autologous bone marrow rescue. Conditioning regimens were ifosphamide plus melphalan for the first autograft and busulfan plus thiotepa for the second. Hematological recovery was prompt, and no severe complications were observed. They are doing well without evidence of recurrence at 19 and 49 months after the second autograft, respectively.

Serum sialic acid and ankle versus brachial arterial-pressure ratio in NIDDM

Serum sialic acid is related to mortality from cardiovascular disease and is increased in patients with diabetic microangiopathies. The purpose of this study was to examine whether serum sialic acid is associated with ischemic disease of the lower extremities, using the ankle versus brachial arterial-pressure ratio. The subjects were NIDDM patients attending diabetic clinics. They received a questionnaire on smoking and duration of diabetes, and physical examinations including measurement of blood pressure of upper and lower extremities. Fasting blood was taken for measurement of sialic acid, total and HDL cholesterol, and HbA1c. Serum sialic acid was significantly correlated with ankle versus brachial arterial-pressure ratio (r = -0.32) and HbA1c (r=0.45). The correlation with ankle versus brachial arterial-pressure ratio was evident in the patients with low ankle versus brachial arterial-pressure ratios (r = -0.66), but was not significant in those with normal ankle versus brachial arterial-pressure ratios (r=0.16). The correlation with HbA1c was significant independently of ankle versus brachial arterial-pressure ratios. Mean serum sialic acid was higher in patients with very low ankle versus brachial arterial-pressure ratios (< 0.9) than in those with normal ankle versus brachial arterial-pressure ratios (> or = 1.0) or slightly low ankle versus brachial arterial-pressure ratios (0.9 approximately 1.0). These results suggest that serum sialic acid reflects the status of blood glucose control and the progression of ischemic disease of the lower extremities in NIDDM patients.

[Phase I Study of RA-700. RA-700 Clinical Study Group]

An antitumor substance, RA-700, isolated from Rubia akane or Rubia cordifolia has the novel structure. Phase I clinical study was conducted by the RA-700 clinical study group consisting of 6 institutions. A single dose administration and 5-day schedule administration were evaluated with 14 patients respectively. RA-700 was given from 0.2 to 1.4 mg/m2 in single i.v. dose study, from 0.4 to 2.0 mg/m2 in 5-day i.v. schedule study. Nausea and vomiting, fever, stomachache, mild hypotension and slight abnormality of electric-cardiogram were observed as the toxicities. In pharmacokinetic study, the elimination half-lives (t1/2) of RA-700 in plasma were 55 min, of alpha-phase and 3.9 hrs. of beta-phase by single dose study, and 23-25 min. of alpha-phase and 6-14 hrs. of beta-phase by 5-day schedule study. Accumulation was not found by 5-day schedule administration, and metabolite were not observed in plasma and urine. It seems that RA-700 is metabolized by the liver and excreted in the feces. In conclusion, the maximum tolerated dose was 1.4 mg/m2 for 5-day schedule administration.

[Fundamental and clinical studies of sulbactam/cefoperazone in the pediatric field]

Fundamental and clinical studies were carried out on sulbactam/cefoperazone (SBT/CPZ) in the field of pediatrics. The following results were obtained: A total of 185 clinical isolates that had been stocked at our department was employed to determine the minimum inhibitory concentrations (MICs) of SBT/CPZ against various bacterial species. SBT/CPZ showed strong antibacterial potency against E. coli, Salmonella, Klebsiella and P. mirabilis, and relatively strong potency against S. marcescens, P. aeruginosa and S. aureus. Antibacterial potency of SBT/CPZ was stronger than that of CPZ alone against E. coli, and it also showed strong activity against strains of Salmonella, S. marcescens and S. aureus, moderately or highly resistant to CPZ. SBT/CPZ was administered by intravenous bolus infusion to pediatric patients to determine the serum concentrations of SBT and CPZ. At a dose of 10 mg/kg the mean serum levels of SBT and CPZ were as follows; 17.8 micrograms/ml, 40.7 micrograms/ml at 15 minutes and 0.3 microgram/ml at 6 hours, respectively. The half-lives of SBT and CPZ in the serum were 1.05 hours and 1.76 hours, respectively. Similarly, at a dose of 20 mg/kg the mean serum levels of SBT and CPZ were; 31.9 micrograms/ml, 81.0 micrograms/ml at 15 minutes and 0.5 microgram/ml, 6.1 micrograms/ml at 6 hours, and the half-lives were 1.00 hour and 1.72 hours, respectively. At a dose of 40 mg/kg, only 1 case was determined. The serum levels of SBT and CPZ were 34.4 micrograms/ml, 74.8 micrograms/ml at 30 minutes and 0.2 microgram/ml at 6 hours, and the half-lives were 0.78 hour and 1.38 hours, respectively. SBT/CPZ was drip-infused intravenously over a period of 1 hour, and the serum concentrations of SBT and CPZ were determined. At the dose of 10 mg/kg or 20 mg/kg, the peak serum levels of SBT and CPZ were observed at 1 hour or at the end of drip infusion. At a dose of 10 mg/kg the mean serum levels of SBT and CPZ were 14.4 micrograms/ml, 33.7 micrograms/ml at 1 hour and 1.4 micrograms/ml, 4.6 micrograms/ml at 7 hours, respectively. The half-lives was 1.86 hours for SBT and 2.23 hours for CPZ, respectively. Similarly at a dose of 20 mg/kg, the mean serum levels of SBT and CPZ were, 22.2 micrograms/ml, 34.6 micrograms/ml at 1 hour and 0.5 microgram/ml, 2.8 micrograms/ml at 7 hours, and the half-lives was 1.17 hours and 1.75 hours, respectively. The urinary recovery rate was determined for the 6 hours period after administration.(ABSTRACT TRUNCATED AT 400 WORDS)

[Basic and clinical studies on ceftazidime in the pediatric field]

Basic and clinical studies were made on ceftazidime (CAZ) in pediatric field, and the following results were obtained. The antibacterial activity of CAZ against clinically isolated and maintained strains was examined. CAZ was unequivocally more active than CEZ and CMZ against Gram-negative rods, with MIC distribution similar to that of CTX, except for that for P. aeruginosa. The MIC of CAZ was lower than that of CTX for P. aeruginosa. Compared with the MICs of CEZ, CMZ and CTX, CAZ showed slightly higher MICs for Gram-positive bacteria. The blood concentrations of CAZ, at 0.25, 0.5, 1, 2, 4 and 6 hours after a one shot intravenous injection of 10 mg/kg of CAZ were 64.9, 36.9, 28.3, 14.7, 4.92 and 2.42 micrograms/ml, respectively, with the half-life of 1.27 hours. The blood concentrations of CAZ, at 0.25, 0.5, 1, 2, 4 and 6 hours after a 1-hour drip infusion of 10 mg/kg of CAZ were 16.6, 24.5, 41.4, 17.1, 5.38 and 2.62 micrograms/ml, respectively, with the half-life of 1.28 hours. The blood concentrations of CAZ, at 0.25, 0.5, 1, 2, 4 and 6 hours after a one shot intravenous injection of 20 mg/kg of CAZ were 73.1, 60.8, 39.3, 17.3, 8.23 and 4.45 micrograms/ml, respectively, with the half-life of 1.42 hours. The blood concentrations of CAZ, at 0.5, 1, 2, 4 and 6 hours after a 1-hour drip infusion of 20 mg/kg of CAZ were 55.1, 69.0, 32.1, 11.4 and 4.56 micrograms/ml, respectively, with the half-life of 1.27 hours. Urinary recovery rate of CAZ during the first 6 hours after a one shot intravenous injection of 10 mg/kg of CAZ was 86.7%. CAZ was administered to 17 children with infections, and the clinical response was excellent or good in 94%. CAZ was bacteriologically effective in 14 patients, all bacteria having been eradicated in them. The bacteria were E. coli in 10 patients, H. influenzae in 2, P. aeruginosa in 1 and S. pneumoniae in 1. As for side effects, slight elevation in GOT was observed in 1 case and eosinophilia, in another case.

[Experimental and clinical evaluation of cefpiramide in pediatrics]

Fundamental and clinical studies on cefpiramide (CPM), a new semisynthetic cephalosporin, were made and the following results were obtained. The antibacterial activities of CPM against clinical isolates were almost similar to those of conventional cephems except for Pseudomonas aeruginosa. The antibacterial activity of CPM against P. aeruginosa was excellent and superior than those of the others. Ten or twenty mg/kg of CPM was given intravenously at one shot to 11 cases. The mean serum levels of CPM reached 231 micrograms/ml at 15 minutes, 119 micrograms/ml at 30 minutes, 88 micrograms/ml at 1 hour, 65 micrograms/ml at 2 hours and 33 micrograms/ml at 6 hours after administration at a single dose of 10 mg/kg, respectively with the half-life of 3.42 hours. In case of 20 mg/kg, the mean serum levels attained 306 micrograms/ml at 15 minutes, 245 micrograms/ml at 30 minutes, 160 micrograms/ml at 1 hour, 118 micrograms/ml at 2 hours and 66 micrograms/ml at 6 hours respectively after administration with the half-life of 5.20 hours. CPM was given intravenously to 12 patients with various bacterial infections. The clinical effects were excellent in 5 cases, good in 6 cases and poor in 1 case and the effective rate was 92%. No side effect was observed in all cases.

[Experimental and clinical studies of an ampicillin suppository (KS-R1) in pediatrics]

Blood levels of ampicillin (ABPC) were measured in 10 childish patients with heart disease after the rectal administration of KS-R1 at doses of 125 mg and 250 mg. Average blood levels of ABPC at 15, 30 minutes, 1, 2 hours and 4 hours after the administration of KS-R1 were 6.8, 6.9, 3.1, 1.1 mcg/ml and 0.1 mcg/ml with half-life of 0.64 hours in patients of age from 1 year to 4 years 7 months old (dose level 8.9 approximately 13.9 mg/kg, average 10.5 mg/kg), and 5.2, 6.1, 3.4, 1.0 mcg/ml and 0.1 mcg/ml with half-life of 0.65 hours in patients of age from 7 years 10 months to 10 years 7 months old (dose level 8.3 approximately 13.9 mg/kg, average 9.8 mg/kg), respectively. Clinical effective rate (excellent and good) was 87% in 55 childish patients with infections. Bacteriologically, 13 strains (74%) out of 18 strains which were isolated from the patients were eradicated. No severe side effects were observed. Diarrhea was observed in 3 cases.

[Experimental and clinical evaluation of cefotetan in pediatrics]

Preclinical studies were carried out on cefotetan (CTT), together with clinical studies in the field of pediatrics. The following results were obtained. A total of 114 clinical isolates that have been stored in the authors' department was employed to determine the minimum inhibitory concentrations (MICs) of CTT against various bacterial species. Against E. coli, Salmonella, K. pneumoniae and P. mirabilis, the MICs of CTT showed a peak at 0.78 micrograms/ml, and most of the strains were inhibited by a CTT concentration of 6.25 micrograms/ml or less. The MICs for S. marcescens strains showed a peak at 25 micrograms/ml, with 25% of the strains having MICs of 3.13 micrograms/ml or less, and 67% having MICs of 25 micrograms/ml or more. All of the P. aeruginosa strains had MICs of over 100 micrograms/ml. Against all of the tested strains of S. aureus, a Gram-positive bacterium, CTT showed MICs of 12.5 micrograms/ml or more, while all of the strains of S. faecalis were found to have MICs of over 100 micrograms/ml. CTT was administered intravenously to pediatric patients as a bolus injection, and then the concentration of the antibiotic in the serum was determined as a function of time. When the dosage rate was 10 mg/kg, the mean serum levels were as follows; 58.2 micrograms/ml at 30 minutes, 45.5 micrograms/ml at 1 hour, 33.6 micrograms/ml at 2 hours, 18.0 micrograms/ml at 4 hours and 11.7 micrograms/ml at 6 hours after the injection. The half-life of CTT in the serum at this dosage was thus 2.40 hours. Similarly, at a dosage rate of 20 mg/kg, the mean values at the various times were; 98.6 micrograms/ml at 30 minutes, 75.6 micrograms/ml at 1 hour, 57.8 micrograms/ml at 2 hours, 35.5 micrograms/ml at 4 hours and 23.2 micrograms/ml at 6 hours subsequent to the injection. The half-life of CTT in the serum in these cases was 2.73 hours. CTT was drip-infused intravenously over a period of 1 hour, and then the serum concentration of the drug was monitored with the passage of time. Subsequent to the administration of 10 mg/kg, the mean serum concentrations were as follows; 48.8 micrograms/ml at 30 minutes, 81.5 micrograms/ml at 1 hour, 42.2 micrograms/ml at 2 hours, 23.6 micrograms/ml at 4 hours and 14.8 micrograms/ml at 6 hours subsequent to the injection. The half-life of CTT in the serum after this intravenous drip infusion was thus 2.13 hours.(ABSTRACT TRUNCATED AT 400 WORDS)

[Pharmacokinetics study on gentamicin intravenous drip infusion in children]

Pharmacokinetics of gentamicin in children after intravenous infusion over 60 minutes were compared with that after intramuscular injection. 1. Mean measured peak serum levels after intravenous infusion of 2.5 mg/kg and intramuscular injection of 2.0 mg/kg were 6.1 micrograms/ml at termination of infusion and 6.5 micrograms/ml at 30 or 60 minutes after injection, respectively. Older children showed higher serum levels. 2. There was no difference in serum half-life between both modes of administration. 3. The AUC after intravenous infusion was slightly larger than that after intramuscular injection. 4. It was suggested that the efficacy and safety of the treatment by intravenous infusion in children are comparable to that by the intramuscular injection, and optimum single dose is 1.5--2.5 mg/kg.

[Basic and clinical studies on cefmenoxime in pediatric field]

Basic and clinical studies were made on cefmenoxime (CMX) in pediatric field, and the following results were obtained. 1. The antibacterial activity of CMX against clinically isolated and maintained strains was examined. CMX had stronger antibacterial activity than CEZ against Escherichia coli, Salmonella, Klebsiella pneumoniae, Proteus mirabilis, Serratia marcescens and Pseudomonas aeruginosa, but CEZ had stronger antibacterial activity against Staphylococcus aureus. 2. The blood concentrations of CMX, 0.5, 1, 2, 4 and 6 hours after a one-shot intravenous injection of 20 mg/kg of CMX were 33.6, 15.1, 4.5, 2.5 and 0.6 mcg/ml, respectively, with the half-life of 1.04 hours. 3. The blood concentrations of CMX, 0.5, 1, 2, 4 and 6 hours after a 1-hour intravenous drip infusion of 20 mg/kg of CMX were 32.0, 55.2, 8.4, 4.2 and 1.0 mcg/ml, respectively, with the half-lite of 0.96 hour. 4. A complete or partial clinical response to therapy with CMX was obtained in all 10 children with infectious diseases. 5. Bacteriological examination made on 3 patients showed that all bacteria had been eradicated, and that therapy was effective. The bacteria were E. coli in 2 patients and Proteus mirabilis in 1 patient. 6. The side effects produced were neutropenia, eosinophilia and skin eruption in 1 patient, and diarrhea in 1 patient.

[Fundamental and clinical evaluation of 9,3"-diacetylmidecamycin in pediatric field (author's transl)]

1. The dry syrup of MOM was administered orally to 17 patients mainly with heart diseases at doses of 10 mg/kg and 20 mg/kg. In 17 cases, the serum level was measured and in 4 cases, the urinary excretion rate including the metabolites of MOM. 2. The mean maximal concentrations were 0.54 mcg/ml at 30 minutes for the group of 10 mg/kg treatment and 0.33 mcg/ml at 1 hour for the group of 20 mg/kg treatment. The dose response was not observed obviously in both groups. 3. In each of the cases, the sum of excretion rates of metabolites in the 24-hour urine was about 1%. 4. MOM was administered clinically to 39 cases with respiratory tract infections and the overall efficacy rate was 85%. 5. In this study, 5 strains of S. pyogenes were isolated and the eradication rate was 60%. 6. Although severe side effects were not observed, gastrointestinal abnormalities like diarrhea and vomiting were seen in 3 cases. 7. Any pediatric patient did not refuse taking.