The electrophysiological properties of jaw-closing motoneurons (JCMNs) in postnatally developing rats aged 4 to 27 days were investigated in slice preparations using intracellular recording techniques. The input resistance of JCMNs from young rats (aged 4-9 days) was greater than that of JCMNs from rats aged 10 days or older. The action potential half-duration progressively decreased with age. The incidence of post-spike afterdepolarization (ADP) progressively increased during postnatal development, whereas the amplitude and half-duration of the medium-duration afterhyperpolarization (mAHP) decreased with age. These findings demonstrate that in rat JCMNs, the input resistance, action potential, ADP and mAHP change during postnatal development. These changes are likely to affect the firing properties of JC-MNs.

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The effect of freezing on fetal DNA fragmentation in maternal plasma, and maternal DNA fragmentation in plasma and urine, was investigated. Seven real-time PCR assays were designed to amplify different-sized amplicons targeting the SRY gene. Fragmentation of fetal DNA in maternal plasma was compared between new and four-year-old samples. With the exception of the smallest amplicon of 107 bp, which is more abundant in aged samples, the relative abundance of amplicons in new and old samples is essentially equivalent. To investigate differences in fragmentation of fetal DNA between plasma and urine from pregnant women, three different-sized amplicons were amplified and DNA fragmentation between plasma and urine was compared. Although fetal DNA in urine was not detected using the 107 and 137 by amplicons of the SRY sequence, fetal DNA using a 63-bp amplicon was detectable in five of seven cases. In conclusion, cell-free fetal DNA in maternal plasma is stable under cryopreservation at -20°C for at least four years. Approximately 60% of fetal DNA in maternal plasma was fragmented to <100 by and fetal DNA in urine was further fragmented. Maternal urine may be suitable for detection of fetal DNA, although a smaller target size is more important for PCR amplification of fetal DNA in urine than in the analysis of plasma from pregnant women.

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To evaluate the learning process of phacoemulsification and aspiration (PEA) with intraocular lens (IOL) implantation by junior and senior ophthalmologists. Five ophthalmologists being trained to perform PEA and IOL implantation through temporal corneal incision were studied. The technique involved surgery with the dominant right hand for the right eye and the non-dominant left hand for the left eye. The time for surgery and energy required for ultrasonic (US) emulsification of the lens were recorded and used to quantitatively evaluate the learning process. The time and energy required for us for the early cases were compared with later cases. The time required for emulsification decreased after training. There were no significant differences in the time required to perform the technique for the right and left hands of four trainees. One trainee required more time to perform the surgery with his left hand, which did not decrease with training. Younger trainees demonstrated a reduction in energy used, whereas older trainees did not, indicating slower learning. The training process could be evaluated quantitatively and then be used for medical education and evaluation of the surgeon.

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Recent studies have demonstrated that adult bone marrow cells have a tremendous capacity to differentiate into the epithelial cells of the liver, lung, gastro-intestinal tract, and pancreas. The migration of endothelial cells could also play a role in the response to pancreatic islet cell injury. To address this issue, we investigated whether transplanted bone marrow cells (BMC) have the capacity to migrate to a damaged pancreas and differentiate into insulin producing cells, thereby restoring tissue function after streptozotocin (STZ) -induced pancreatic β-cell injury in vivo. Whole bone marrow cells labeled with PKH26 were infused intravenously into syngenic STZ-treated diabetic rats. At each time point, the expression of insulin in bone marrow-derived cells was examined in immunohistochemical studies, and plasma insulin and glucose levels were measured. Donor-derived bone marrow cells were positive for insulin immunoreactivity in the recipient pancreas. In addition, bone marrow-derived cells migrated into the damaged pancreas and synthesized insulin. BMC administration partially increased the plasma insulin concentration, reduced the plasma glucose concentration, and reduced the mortality rates of STZ-treated diabetic rats. In conclusion, our study revealed that bone marrow-derived cells have a capacity for insulin production, following recruitment to the site of pancreatic β-cell injury.

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Pierre Robin Sequence (PRS) is a birth defect characterized by an abnormally small lower jaw. The aim of this study was to compare the craniofacial morphology of Japanese PRS patients with that of patients with isolated cleft palate (ICP) . Eleven pre-adolescent children with PRS (mean age, 7.0 years ; range, 4.1-11.0 years) and 22 children with ICP (mean age, 7.2 years ; range 5.3-9.1 years) were involved in the study. Measurements were taken from standard lateral cephalometric radiographs. Six of the PRS patients had also undergone longitudinal lateral cephalograms, which allowed us to assess changes that occurred with growth. In PRS patients, the mandible was significantly smaller, more recessive and posteriorly rotated compared to the mandible of ICP patients. The curve of the mandibular baseline in PRS patients had a distinctive shape not seen in ICP cases. The lower sagittal depth of the pharynx was significantly shorter in patients with PRS than in those with ICE In the majority of the longitudinally-assessed PRS patients, the craniofacial characteristics became more pronounced with time. Our findings highlight the necessity for developing new and early orthodontic treatments for PRS, because spontaneous improvement through growth does not appear to be a likely outcome.

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A thorough understanding of the hip joint is necessary for prediction and prevention of hip osteoarthritis (OA) . The hip joint is commonly evaluated using X rays, arthrograms, arthroscopic findings and magnetic resonance imaging. Two-dimensional pelvic computed tomography (CT) has also been used, but its clinical relevance has not been studied sufficiently. The aim of this investigation was to evaluate the effectiveness of pelvic CT, especially during prearthrosis and early coxarthrosis, for estimation of the progression in hip OA. Acetabular sector angles were measured in normal (n=29), prearthrosis (n=81), and early coxarthrosis (n=61) . The findings suggest that the posterior regions of the acetabulum deteriorate more than the anterior regions as arthritis progresses, as shown by comparing the posterior acetabular sector angle (normal, mean ± SD, 102.5° ± 9.3°; prearthrosis, 93.3°± 7.0°; early coxar-throsis, 90.9°± 9.6°) with the anterior acetabular sector angle (normal, 55.5°± 9.4°; prearthrosis, 49.2°± 8.1°; early coxarthrosis, 50.5°± 11.9°) . In addition, the HASA, which shows the general size of the acetabulum, was smaller in the more arthritic hips (normal, 158.0°± 12.9°, prearthrosis, 142.5°± 10.9°, early cox arthrosis, 141.4°± 17.6°) . This suggests that a small acetabulum, and especially posterior dysplasia, may be a risk factor in the progression from normal to prearthrosis and early coxarthrosis. We propose that the posterior acetabulum plays a relatively important role in the progression of hip osteoarthritis, and that its significance for the condition has previously been underestimated.

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In this study we examined whether nitric oxide (NO) expression in various areas of the rat brain is affected in a model of ethanol dependency. We compared the effects of ethanol administered in single or repetitive doses (by oral gavage and ad libitum) on NO concentration the brain, in the presence and absence of intraperitoneally-injected NO synthase (NOS) inhibitors N G-nitro-L-arginine methyl ester (L-NAME) and 7 nitroindazole (7-NI) . NO was quantified by detecting NO^2-, using a NO^2-/ NO^3- assay kit. The NO levels were significantly higher with repetitive ethanol administration, compared to saline-administered controls, in all parts of the rat brain. The NO levels in the brains of rats given single doses of ethanol were significantly greater than in controls, except in the hypothalamus. These differences were reduced by treatment with 7 NI (a selective nNOS inhibitor) . We conclude that ethanol administration increases NO levels in the rat brain, and that these increases are mainly produced by nNOS. We propose that elevated NO levels in the hypothalamus, which are particularly marked with repetitive ethanol administration, activate the hypothalamic-pituitary-adrenal axis, resulting in the development of alcohol dependence.

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