In vivo screening of subcutaneous tolerability for the development of novel excipients.

To develop safe subcutaneous formulations and minimize the risk of local irritation, it is essential to optimize the composition of active pharmaceutical ingredients and excipients. Depending on the physicochemical properties of the active pharmaceutical ingredient, additional excipients may be required to improve the stability and solubility of the active pharmaceutical ingredient. However, some of these excipients may not have been previously used in injectable drugs. Owing to the lack of safety data for such excipients, especially those used in subcutaneous dosing, it is important to evaluate their potential for local irritation during the early stages of formulation development. We evaluated the tolerability of 44 formulations with 24 candidate novel excipients, such as surfactants, polymers, and lipids, in a single subcutaneous dose in rats. Excipient formulations were administered as single bolus subcutaneous injections with an injection volume of 1 mL. The injection sites were observed for 2 days, and macroscopic and microscopic examinations were conducted. Local tolerability was evaluated on the basis of severity, incidence, and pathophysiology of each finding. Formulations that caused tissue degeneration or necrosis, which is indicative of tissue injury, were determined to be irritative and poorly tolerated. A single-dose subcutaneous screening study in rats was considered effective in ranking the safety of candidate excipients during the formulation optimization phase.

[Home Medical Care Promotion for Multidisciplinary Cooperation].

It may be said that the effective functioning of an integrated community care system depends entirely on home medical care. "Cooperation"is necessary in pushing home medical care forward and it is vital to advance as a system. In Iwaki-city, the municipal government and the medical association have been sponsoring many types of multidisciplinary cooperation workshops for home medical-care promotion. There was administrative participation, and cooperation became the main workshop focus. We hold workshops 2 times a year. The Iwaki City Medical Association holds lectures on home medical care in the town. Doctors who work in medical offices and hospitals attend the lectures, with topics such as family medicine, understanding dementia, advice for the acceptance of medical examination, cancer screening in the local community hall, and gaining a favorable reception. In our hospital, I hold many types of workshops on home medical care in southern Iwaki-city and on facilitating cooperation. These contribute to collaboration, as they facilitate face-to-face interaction in an important area. I also report the actions taken in our hospital.

Long-term maintenance of human induced pluripotent stem cells by automated cell culture system.

Pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem (iPS) cells, are regarded as new sources for cell replacement therapy. These cells can unlimitedly expand under undifferentiated conditions and be differentiated into multiple cell types. Automated culture systems enable the large-scale production of cells. In addition to reducing the time and effort of researchers, an automated culture system improves the reproducibility of cell cultures. In the present study, we newly designed a fully automated cell culture system for human iPS maintenance. Using an automated culture system, hiPS cells maintained their undifferentiated state for 60 days. Automatically prepared hiPS cells had a potency of differentiation into three germ layer cells including dopaminergic neurons and pancreatic cells.

Historical control data on developmental toxicity studies in rodents.

Historical control data on rodent developmental toxicity studies, performed between 1994 and 2010, were obtained from 19 laboratories in Japan, including 10 pharmaceutical and chemical companies and nine contract research organizations. Rats, mice, and hamsters were used for developmental toxicity studies. Data included maternal reproductive findings at terminal cesarean sections and fetal findings including the spontaneous incidences of external, visceral, and skeletal anomalies. No noticeable differences were observed in maternal reproductive data between laboratories. Inter-laboratory variations in the incidences of fetuses with anomalies appeared to be due to differences in the selection of observation parameters, observation criteria, classification of the findings, and terminology of fetal alterations. Historical control data are useful for the appropriate interpretation of experimental results and evaluation of the effects of chemical on reproductive and developmental toxicities.

Effects of thalidomide on Fgf8, Bmp4 and Hoxa11 expression in the limb bud in Kbl:JW rabbit embryos.

Thalidomide (TM) induces limb defects in humans and some animal species including rabbits. Although the mechanism of TM-induced limb defects has been investigated for a long period, the limb development-related genes expressions have not been vigorously characterized in rabbits. In this study, we investigated the Fgf8, Bmp4 and Hoxa11 expressions in TM-treated JW rabbit embryos on gestation days (GDs) 10, 11 and 12 by whole mount in situ hybridization. On GDs 10 and 11, growth retardation of the embryo was induced by TM treatment. The Fgf8 expression lengths on GDs 10 and 11 in the forelimb bud were significantly or tended to be decreased in the TM-treated embryos, which was correlated to the growth retardation and was not considered to be directly relevant to the teratogenic effect of TM in the forelimb. The TM-induced characteristic changes in the expression pattern of Hoxa11 and Bmp4 on GDs 10 and/or 11 were not noted. On GD 12, TM-induced growth retardation was not noted and the Fgf8 and Bmp4 expressions were not changed. On the contrary, Hoxa11 expression was narrowed at the anterior region, which was located on the radial side, and was not changed at the middle and posterior regions in the forelimb bud and in all regions in the hindlimb bud. Because the radius malformations were induced by TM treatment, we concluded the decrease in the Hoxa11 expression was related to the TM-induced limb defects and can be a good marker for early prediction of the teratogenic effect of TM.

Historical control data on prenatal developmental toxicity studies in rabbits.

Historical control data on rabbit prenatal developmental toxicity studies, performed between 1994-2010, were obtained from 20 laboratories, including 11 pharmaceutical and chemical companies and nine contract laboratories, in Japan. In this paper, data were incorporated from a laboratory if the information was based on 10 studies or more. Japanese White rabbits and New Zealand White rabbits were used for prenatal developmental toxicity studies. The data included maternal reproductive findings at terminal cesarean sections and fetal findings including spontaneous incidences of morphological alterations. No noticeable differences between strains or laboratories were observed in the maternal reproductive and fetal developmental data. The inter-laboratory variations in the incidences of fetal external, visceral, and skeletal alterations seem to be due to differences in the selection of observation parameters, observation criteria, and classification of the findings, and terminology of fetal alterations.

Maternal age and reproductive function in female Sprague-Dawley rats.

We investigated the age-related changes in reproductive function in female rats of the Crl:CD(SD) strain. The estrous cycles were monitored from 6 to 42 weeks of age. Other females were mated with males at 6, 8, 10, 15, 19, 23, 27, 31, 35 and 40 weeks of age and caesarean section was performed on day 20 of gestation to examine their fetuses, and then reproductive parameters were calculated and fetal growth was observed. The percentage of rats exhibiting irregular estrous cycles increased from 23 weeks of age. The copulatory and fertility indices decreased from 35 and 27 weeks of age, respectively. Dams at 6 weeks of age showed low numbers of corpora lutea and implantation sites. Although the number of corpora lutea was not affected by advanced maternal age, number of implantation sites decreased from 27 weeks of age. The pre- and post-implantation loss rates increased from 23 and 31 weeks of age, respectively, and the number of live fetuses decreased from 27 weeks of age. Fetal growth retardation was observed in maternal rats older than 31 weeks of age. The external observations on the fetuses revealed umbilical hernia at 35 to 40 weeks of age. These data indicated that maternal aging affected reproductive function and fetal development from 23 and 31 weeks of age, respectively. It was considered that the appropriate age of Crl:CD(SD) female rats for the assessment of reproductive toxicity were 8 to 22 weeks.