Effects of hyperbaric oxygen on GDNF expression and apoptosis in spinal cord injury

The effects of hyperbaric oxygen treatment on the progress of secondary damage following traumatic spinal cord injury were investigated. The early onset of hyperbaric oxygen treatment significantly diminished the number of apoptotic cells 1 day after the injury. However, hyperbaric oxygen did not influence the proliferation of macrophages or activated microglia. The gene expression of glial cell line-derived neurotrophic factor (GDNF) and inducible nitric oxide synthetase (iNOS) was significantly attenuated 1 day after the injury in the hyperbaric oxygen groups compared with the control group. The down-regulation was confirmed by immunohistochemical staining. Early hyperbaric oxygen treatment was shown to effectively suppress the progress of apoptosis perhaps via the inhibition of iNOS gene despite the down-regulation of the GDNF gene.     

Association between cognitive function and olfactory identification ability in community-dwelling older individuals

[Purpose] We investigated whether olfactory identification ability may be useful for early detection of cognitive decline. [Participants and Methods] The study included 55 community-dwelling older individuals without a history of mild cognitive impairment or dementia, who were capable of living independently. Cognitive function was evaluated using the Japanese versions of the Mini-Mental State Examination and the Montreal Cognitive Assessment tools. The olfactory identification ability was evaluated using the Odor Stick Identification Test for the Japanese. We also investigated the association between olfactory identification ability and cognitive function. [Results] Based on the Japanese version of the Mini-Mental State Examination, all participants were categorized into the noncognitive decline group, and based on the Japanese version of the Montreal Cognitive Assessment tool, 21 participants were categorized into the cognitive decline group. With regard to olfactory discrimination ability, we observed a significant difference between participants with and without cognitive decline based on the Japanese version of the Montreal Cognitive Assessment scores. Furthermore, we observed a significant positive correlation between the Japanese version of the the Montreal Cognitive Assessment scores and the Odor Stick Identification Test for the Japanese scores, although no significant correlation was observed between the Japanese version of the Mini-Mental State Examination and the Odor Stick Identification Test for the Japanese scores. [Conclusion] Olfactory identification ability may be useful to detect early-stage cognitive decline in community-dwelling older individuals.     

The ontogeny of the interleukin 2 receptor expression and of the interleukin 2 responsiveness in the rat thymus

The ontogeny of the interleukin 2 receptor (IL 2 R) expression and of the IL 2 responsiveness has been investigated in the rat thymus. In tissue sections, IL 2 R-bearing cells were first detected at day 16 of gestation using the anti-IL 2 R mAb ART-18. In contrast to mice, IL 2 R-bearing cells of the rat are localized mainly in the thymic medulla from the first day of the corticomedullary compartimentalization, and not in the cortex. They are found in regions with a high expression of MHC class II antigens. The proportion of IL 2 R-bearing cells increases during gestation, reaches a peak at the first day after birth and declines to the adult level in the following weeks. The appearance of medullary localized IL 2 R-bearing cells is paralleled with the capacity of the thymocytes to proliferate in response to IL 2 without any additional stimuli.     

Isolation and characterization of human anterior cruciate ligament-derived vascular stem cells

The anterior cruciate ligament (ACL) usually fails to heal after rupture mainly due to the inability of the cells within the ACL tissue to establish an adequate healing process, making graft reconstruction surgery a necessity. However, some reports have shown that there is a healing potential of ACL with primary suture repair. Although some reports showed the existence of mesenchymal stem cell-like cells in human ACL tissues, their origin still remains unclear. Recently, blood vessels have been reported to represent a rich supply of stem/progenitor cells with a characteristic expression of CD34 and CD146. In this study, we attempted to validate the hypothesis that CD34- and CD146-expressing vascular cells exist in hACL tissues, have a potential for multi-lineage differentiation, and are recruited to the rupture site to participate in the intrinsic healing of injured ACL. Immunohistochemistry and flow cytometry analysis of hACL tissues demonstrated that it contains significantly more CD34 and CD146-positive cells in the ACL ruptured site compared with the noninjured midsubstance. CD34+CD45- cells isolated from ACL ruptured site showed higher expansionary potentials than CD146+CD45- and CD34-CD146-CD45- cells, and displayed higher differentiation potentials into osteogenic, adipogenic, and angiogenic lineages than the other cell populations. Immunohistochemistry of fetal and adult hACL tissues demonstrated a higher number of CD34 and CD146-positive cells in the ACL septum region compared with the midsubstance. In conclusion, our findings suggest that the ACL septum region contains a population of vascular-derived stem cells that may contribute to ligament regeneration and repair at the site of rupture.