597 research outputs found
Study on Vortex States in High-T_c Oxide Superconductor YBa_2Cu_3O_y by Scanning Tunneling Spectroscopy(Abstracts of Doctoral Dissertations,Annual Report(from April 2002 to March 2003))
Leukemia autopsies in Japan
For the purpose to know whether the annual increase of leukemia incidence in Japan is due to some leukemogenic factors or due to the increased detection
rate, the authors made some statistical survey of autopsy cases in which the
diagnosis is reliable and not any type of leukemias escape the detection. The
results showed that acute leukemias, which are found mostly in younger age, is
actually increasing. In addition, it has been deduced that among the suspected
factors the increase in ionizing radiation will be one of the most probable factors
for the increase in leukemia incidence</p
Production of Al-based composite materials including stress-luminescent particles using 3-dimensional penetration casting (3DPC)
A stress-luminescent powder can be applied as sensors because of luminous characteristic under stress. Key point in fabrication is how uniformly to disperse powders in metallic matrix. Three-dimensional penetration casting (3DPC) process is a good application to fabricate the composite materials using stress-luminescent powders and molten Al. A commercial stress-luminescent powder was prepared (a)stress- luminescent powders (Taikourozai Co.) and (b)EZ bright (EZ bright Cooperation). 3DPC process was conducted using a special mould has dimensions of 42mm height and 30mm diameter. Mould was heated up to 750°C before 3DPC. After 3DPC, particles were well dispersed in Al matrix without crack generations with optical microscopy observation. Also, samples were emitted when they were pressed and scratched
Functional training after orthognathic surgery
Background/purpose: Even after surgical orthodontic treatment, the level of masticatory function in patients with jaw deformities is still lower than that of healthy subjects. The purpose of this study was to evaluate the effects of functional training program using gum chewing exercise after orthognathic surgery on masticatory function in patients with mandibular prognathism.
Materials and methods: The study subjects were 16 patients with mandibular prognathism who underwent orthognathic surgery and 8 individuals with normal occlusion. Patients were divided into two groups (training group and non-training group; n = 8 per group). Functional training included gum chewing exercise and patient-education about masticatory function. The training; gum chewing exercise of 5 min twice a day for 90 days, started at 3 months after surgery. For each subject, electromyographic activities of masseter and temporalis muscles during maximum voluntary clenching (MVC) and jaw movement during gum chewing were recorded before and after surgical orthodontic treatment. Two parameters; activity index (AI: ratio of activity of masseter and temporalis muscles) and error index (EI: ratio of the number of abnormal chewing patterns), were used.
Results: In the training group, the AI value during MVC increased significantly and the EI value during gam chewing decreased significantly after surgical orthodontic treatment (AI: p < 0.01; EI: p < 0.01), indicating the improvement of activity balance of masseter and temporalis muscles and conversion of the jaw movement from abnormal to normal pattern (p < 0.01).
Conclusion: Our findings suggested that functional training using the gum chewing and patient-education exercise improved masticatory function in patients with mandibular prognathism
The Animal Model of Spinal Cord Injury as an Experimental Pain Model
Pain, which remains largely unsolved, is one of the most crucial problems for spinal cord injury patients. Due to sensory problems, as well as motor dysfunctions, spinal cord injury research has proven to be complex and difficult. Furthermore, many types of pain are associated with spinal cord injury, such as neuropathic, visceral, and musculoskeletal pain. Many animal models of spinal cord injury exist to emulate clinical situations, which could help to determine common mechanisms of pathology. However, results can be easily misunderstood and falsely interpreted. Therefore, it is important to fully understand the symptoms of human spinal cord injury, as well as the various spinal cord injury models and the possible pathologies. The present paper summarizes results from animal models of spinal cord injury, as well as the most effective use of these models
Treatment decision of camouflage or surgical orthodontic treatment for skeletal Class III patients based on analysis of masticatory function
Background/purpose: Surgical orthodontic treatment is recommended for patients with severe dentoskeletal discrepancies, while camouflage orthodontic treatment is recommended for patients with mild to moderate discrepancies. However, the decision as to which treatment should be chosen is complicated. The purpose of this study was to determine differences in masticatory function in patients who underwent camouflage and surgical orthodontic treatment for skeletal Class III malocclusion, as well as the usefulness of Wits appraisal in treatment decision based on masticatory functional analysis.
Materials and methods: The study subjects were 45 patients with skeletal Class III malocclusion (15 cases with camouflage orthodontics and 30 cases with orthognatic surgery) and 12 individuals with normal occlusion. We analyzed the pre-treatment records of electromyographic activities of masseter and temporalis muscles and jaw movements.
Results: There were no significant differences in various functional measurements between the camouflage and surgery groups. However, there were significant but not strong correlations between ANB and both masseter muscle activity (r = 0.36, p < 0.01) and expression ratio of abnormal chewing (r = −0.54, p < 0.01). Division of patients into two groups using a cutoff value of −6.0 mm for Wits appraisal showed a significant difference in masseter muscle activity between −6.0 mm or less group and the control (p < 0.01) but none between more than −6.0 mm group and the control.
Conclusion: Camouflage orthodontic treatment is inappropriate for patients with relatively severe dentoskeletal discrepancies. Wits appraisal of −6.0 mm is a potentially useful parameter for treatment decision
Identification of lactate dehydrogenase as a mammalian pyrroloquinoline quinone (PQQ)-binding protein
Pyrroloquinoline quinone (PQQ), a redox-active o-quinone, is an important nutrient involved in numerous physiological and biochemical processes in mammals. Despite such beneficial functions, the underlying molecular mechanisms remain to be established. In the present study, using PQQ-immobilized Sepharose beads as a probe, we examined the presence of protein(s) that are capable of binding PQQ in mouse NIH/3T3 fibroblasts and identified five cellular proteins, including l-lactate dehydrogenase (LDH) A chain, as potential mammalian PQQ-binding proteins. In vitro studies using a purified rabbit muscle LDH show that PQQ inhibits the formation of lactate from pyruvate in the presence of NADH (forward reaction), whereas it enhances the conversion of lactate to pyruvate in the presence of NAD+ (reverse reaction). The molecular mechanism underlying PQQ-mediated regulation of LDH activity is attributed to the oxidation of NADH to NAD+ by PQQ. Indeed, the PQQ-bound LDH oxidizes NADH, generating NAD+, and significantly catalyzes the conversion of lactate to pyruvate. Furthermore, PQQ attenuates cellular lactate release and increases intracellular ATP levels in the NIH/3T3 fibroblasts. Our results suggest that PQQ, modulating LDH activity to facilitate pyruvate formation through its redox-cycling activity, may be involved in the enhanced energy production via mitochondrial TCA cycle and oxidative phosphorylation
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