Molecular Analysis of Salivary Gland Branching Morphogenesis

AbstractRecently, clinicians and scientists have focused on tissue engineering for regenerative medical therapy. This approach promises to provide remarkable clinical breakthroughs for the future. In oral and craniofacial medicine, most scientific approaches to tissue engineering currently involve tooth and bone, while little progress has been made toward regenerating organs such as salivary gland. To develop strategies for salivary gland regeneration, it will be important to understand the molecular mechanisms of normal salivary development. This mini-review describes a recently developed and tested set of approaches for identifying and characterizing molecules essential for branching morphogenesis and other developmental processes. It shows the value of using laser microdissection and the new process of T7-SAGE for gene discovery of putative candidate molecules that may be crucial regulators or mediators. We describe a stepwise series of associated strategies for reliable identification and functional testing of a candidate molecule, as well as its successful application to a specific candidate molecule originally identified by T7-SAGE

Model simulations of chemical effects of sprites in relation with observed HO2 enhancements over sprite-producing thunderstorms

Recently, measurements by the Superconducting Submillimeter-Wave Limb Emission Sounder (SMILES) satellite instrument have been presented which indicate an increase in mesospheric HO2 above sprite-producing thunderstorms. The aim of this paper is to compare these observations to model simulations of chemical sprite effects. A plasma chemistry model in combination with a vertical transport module was used to simulate the impact of a streamer discharge in the altitude range 70–80 km, corresponding to one of the observed sprite events. Additionally, a horizontal transport and dispersion model was used to simulate advection and expansion of the sprite air masses. The model simulations predict a production of hydrogen radicals mainly due to reactions of proton hydrates formed after the electrical discharge. The net effect is a conversion of water molecules into H+OH. This leads to increasing HO2 concentrations a few hours after the electric breakdown. Due to the modelled long-lasting increase in HO2 after a sprite discharge, an accumulation of HO2 produced by several sprites appears possible. However, the number of sprites needed to explain the observed HO2 enhancements is unrealistically large. At least for the lower measurement tangent heights, the production mechanism of HO2 predicted by the model might contribute to the observed enhancements

Age and sex differences in various stepping movements of the elderly.

金沢大学人間社会研究域人間科学系Aim: This study aimed to examine sex and age differences of various stepping movements in the elderly and to clarify useful stepping movements for evaluation of their dynamic balance. Methods: Two hundred and eighty-six healthy elderly subjects who could walk independently (male mean age = 71.2 ± 7.1 years; female mean age = 71.5 ± 6.0) performed the following stepping tests: back and forth; up and down with a 5 cm tall step; and in-place stepping matching three tempos (44, 66 and 132 b.p.m.). Step number, single and double support times in the former two stepping tests, and time difference between metronome sound and grounding time in the latter tempo stepping tests were selected as evaluation parameters. Results: An insignificant sex difference was found in all parameters. Hence, the data of men and women was pooled to examine age differences. Significant age differences were found in the step number and double support time of back and forth and up and down stepping tests and in the time difference of three tempo stepping tests. The step number in younger age groups and the support times in older age groups tended to be larger. Conclusion: No sex difference was found in evaluation parameters of all stepping tests, and all parameters tended to be superior in the younger elderly. The elderly experienced more difficulty matching slow tempos than fast tempos in the in-place stepping test. The back and forth, up and down and in-place matching tempo stepping tests may be useful for evaluating dynamic balance ability of the elderly. © 2008 Japan Geriatrics Society

Severity of injuries associated with falls in the community dwelling elderly are not affected by fall characteristics and physical function level

Many elderly people experience difficulty with independent living after injuries associated with falls. This study aimed to examine the influence of fall characteristics and physical function level on the severity of fall related injuries. The surveys were conducted in 1955 community dwelling elderly. The questions regarded the following: fall experience within the past year, fall direction, fall cause, injured parts and degree of injury, and an activity of daily living (ADL) questionnaire from the Ministry of Education, Culture, Sports, Science and Technology Japan. Data of 1850 subjects with available and complete responses were used for analysis. Three hundred and eighty-six (20.9%) elderly people experienced a fall within the past year and 257 (66.7%) were injured. ADL score was significantly higher in the elderly without fall experience than the elderly with fall experience. No significant difference was found in frequency of fall cause and fall direction between the elderly with and without injuries caused by falling. Significant correlations were found between fall direction and fall cause and injured parts (φ=. 0.49 and 0.32). ADL score of the elderly who fell by leg backlash was significantly lower than that of the elderly who fell by tripping, slipping and staggering. A decrease of ADL affects the rate of falls in the elderly, but not the degree of injury. Fall characteristics may not be related to the extent of fall injury. © 2011 Elsevier Ireland Ltd

Comparison of oxygenation kinetics measured by different placements of the NIRS probe during sustained isometric gripping

金沢大学人間社会研究域人間科学系福井大学医学部The purpose of this study was to compare oxygenation kinetics measured by slightly different placements of a near-infrared spectroscopy (NIRS) probe during sustained isometric gripping. Oxygenation kinetics of sixteen young adult males was measured with two NIRS probes attached to the flexor carpiradialis muscle during gripping for 3 min. One probe (channel 1) was attached at one-third the length of a line from the medial epicondyle of the humerus to the styloid process of radius. Another probe (channel 2) was attached at the palmaris longus. Although the cross-correlation coefficients for the two probe placements regarding oxygenated hemoglobin (oxy-Hb/Mb), deoxygenated hemoglobin (deoxy-Hb/Mb) and tissue oxygenation saturation (StO2) were low (rxy, 0.119-0.405), Pearson\u27s correlation coefficients for the times to reach almost steady state for these parameters were very high (oxy-Hb/Mb, r=0.878; deoxy-Hb/Mb, r=0.769; StO2, r=0.843; p<0.05). The difference of oxygenation kinetics between the probe placements may reflect the difference of fiber recruitment characteristics in the flexion muscle group. In conclusion, to obtain a stable measurement, it is important that the NIRS probe is placed at the same anatomical point. © Springer-Verlag Italia 2007

Oral pathobiont induces systemic inflammation and metabolic changes associated with alteration of gut microbiota.

Periodontitis has been implicated as a risk factor for metabolic disorders such as type 2 diabetes, atherosclerotic vascular diseases, and non-alcoholic fatty liver disease. Although bacteremias from dental plaque and/or elevated circulating inflammatory cytokines emanating from the inflamed gingiva are suspected mechanisms linking periodontitis and these diseases, direct evidence is lacking. We hypothesize that disturbances of the gut microbiota by swallowed bacteria induce a metabolic endotoxemia leading metabolic disorders. To investigate this hypothesis, changes in the gut microbiota, insulin and glucose intolerance, and levels of tissue inflammation were analysed in mice after oral administration of Porphyromonas gingivalis, a representative periodontopathogens. Pyrosequencing revealed that the population belonging to Bacteroidales was significantly elevated in P. gingivalis-administered mice which coincided with increases in insulin resistance and systemic inflammation. In P. gingivalis-administered mice blood endotoxin levels tended to be higher, whereas gene expression of tight junction proteins in the ileum was significantly decreased. These results provide a new paradigm for the interrelationship between periodontitis and systemic diseases

Trabecular health of vertebrae based on anisotropy in trabecular architecture and collagen/apatite micro-arrangement after implantation of intervertebral fusion cages in the sheep spine

Healthy trabecular bone shows highly anisotropic trabecular architecture and the preferential orientation of collagen and apatite inside a trabecula, both of which are predominantly directed along the cephalocaudal axis. This makes trabecular bone stiff in the principally loaded direction (cephalocaudal axis). However, changes in these anisotropic trabecular characteristics after the insertion of implant devices remain unclear. We defined the trabecular architectural anisotropy and the preferential orientation of collagen and apatite as parameters of trabecular bone health. In the present study, we analyzed these parameters after the implantation of two types of intervertebral fusion cages, open and closed box-type cages, into sheep spines for 2 and 4 months. Alteration and evolution of trabecular health around and inside the cages depended on the cage type and implantation duration. At the boundary region, the values of trabecular architectural anisotropy and apatite orientation for the closed-type cages were similar to those for isotropic conditions. In contrast, significantly larger anisotropy was found for open-type cages, indicating that the open-type cage tended to maintain trabecular anisotropy. Inside the open-type cage, trabecular architectural anisotropy and apatite orientation significantly increased with time after implantation. Assessing trabecular anisotropy might be useful for the evaluation of trabecular health and the validation and refinement of implant designs.Ishimoto T., Yamada K., Takahashi H., et al. Trabecular health of vertebrae based on anisotropy in trabecular architecture and collagen/apatite micro-arrangement after implantation of intervertebral fusion cages in the sheep spine. Bone, 108, 25. https://doi.org/10.1016/j.bone.2017.12.012

Clinical characteristics of elderly depressive patients with low metaiodobenzylguanidine uptake

BACKGROUND: Recently, depression with Lewy body pathology before the appearance of parkinsonism and cognitive dysfunction has been drawing attention. Low cardiac metaiodobenzylguanidine (MIBG) uptake is helpful for early differentiation of Lewy body disease (LBD) from late-onset psychiatric disorders even before parkinsonism or dementia appears. In this study, we used MIBG uptake as a tool in suspected LBD, and evaluated the relationship of MIBG results to clinical characteristics and depressive symptoms. METHODS: Fifty-two elderly inpatients with depression were included in this study. The Hamilton Depression Rating Scale (HDRS) was administered at admission, and 123 I-MIBG cardiac scintigraphy was performed. Of 52 patients, 38 had normal and 14 had reduced MIBG uptake. RESULTS: Correlation analyses of the late phase heart-to-mediastinum (H/M) ratio on the MIBG test and each item of the HDRS revealed that the H/M ratio was significantly correlated with scores of 'agitation', 'anxiety-somatic', and 'retardation' on the HDRS. Mean HDRS composite scores of 'somatic and psychic anxiety (Marcos)' and 'somatic anxiety/somatization factor (Pancheri)' were higher in the low uptake group than in the normal uptake group. CONCLUSION: Elderly patients with depression who manifested an obvious somatic anxiety tend to show low MIBG uptake, and are more likely to have Lewy body pathology