Aoki M.,Gifu University |
Sakaida Y.,Gifu University |
Tanaka K.,Gifu University |
Mizuta K.,Gifu University of Medical Science |
Ito Y.,Gifu University
Experimental Brain Research | Year: 2012
There is little definitive evidence of the clinical significance of the vestibular-cardiovascular reflex in humans, despite the fact that the vestibular system is known to contribute to cardiovascular control in animals. The present study involved 248 dizzy patients (127 male patients and 121 female patients) aged 65 years and younger. We classi-fied all participants into three groups based on their vestibular evoked myogenic potential (VEMP) responses; absent VEMP, asymmetry VEMP and normal VEMP. To investigate the effect of the otolith disorder, which was estimated by the VEMP, on the orthostatic blood pressure responses, the subjects' systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate were monitored during the orthostatic test after they actively stood up. The male patients in the absent VEMP group had a significant drop in their DBP at 1 min after active standing up (P < 0.05) without any change in their SBP. Conversely, male patients in the asymmetry VEMP and normal VEMP groups showed a significant increase in the SBP at 1 min after active standing up (P < 0.05). Female patients in the absent VEMP group did not show any significant drop in their blood pressure after standing up (P > 0.05). In the entire group of participants, a total of 19.6% of the patients in the absent VEMP group fulfilled the criteria for orthostatic hypotension (OH), which was significantly < the 8.6% of patients in the normal VEMP group and the 7.2% in the asymmetry VEMP group (P < 0.05). Our results suggest that vestibular disorders due to the dysfunction of otolith organs provoke OH. © Springer-Verlag 2011.
Tanaka K.,Gifu University of Medical Science |
Nagao D.,Gifu University of Medical Science |
Okada K.,Gifu University of Medical Science |
Nakamura K.,Gifu University of Medical Science
Aerospace Medicine and Human Performance | Year: 2017
Introduction: The extravehicular activity suit currently used by the United States in space includes a liquid cooling and ventilation garment (LCVG) that controls thermal conditions. Previously, we demonstrated that self-perspiration for evaporative cooling (SPEC) garment effectively lowers skin temperature without raising humidity in the garment. However, the cooling effect is delayed until a sufficient dose of water permeates and evaporates. In the present study, we hypothesized that wearer-controlled vaporization improves the cooling effect. Methods: Six healthy subjects rode a cycle ergometer under loads of 30, 60, 90, and 120 W for durations of 3 min each. Skin temperature and humidity on the back were measured continuously. Subjects wore and tested three garments: 1) a spandex garment without any cooling device (Normal); 2) a simulated LCVG (s-LCVG) or spandex garment knitted with a vinyl tube for flowing and permeating water; and 3) a garment that allowed wearer-controlled vaporization (SPEC-W). Results: The use of s-LCVG reduced skin temperature by 1.57 ± 0.14°C during 12 min of cooling. Wearer-controlled vaporization of the SPEC-W effectively and significantly lowered skin temperature from the start to the end of cycle exercise. This decrease was significantly larger than that achieved using s-LCVG. Humidity in the SPEC-W was significantly lower than that in s-LCVG. Discussion: This preliminary study suggests that SPEC-W is effective in lowering skin temperature without raising humidity in the garment. The authors think it would be useful in improving the design of a cooling system for extravehicular activity. © by the Aerospace Medical Association, Alexandria, VA.
Liu J.,Shenyang University |
Wu J.,Harbin Medical University |
Wang B.,Centers for Disease Control and Prevention |
Zeng S.,Shenyang University |
And 4 more authors.
Journal of Medical Virology | Year: 2014
It is well accepted that vaccination by oral administration has many advantages over injected parenteral immunization. The present study focuses on whether oral vaccination with a DNA vaccine could induce protective immunity against respiratory challenge infection. The M1 gene of influenza A virus was used to construct DNA vaccine using pcDNA 3.1(+) plasmid, a eukaryotic expression vector. The cationic liposomes were used to deliver the constructed DNA vaccine. In vitro and in vivo expression of M1 gene was observed in the cell line and in the intestine of orally vaccinated C57BL/6 mice, respectively. It became clear that this type of oral DNA vaccination was capable of inducing both humoral and cellular immune responses, together with an augmentation of IFN-γ production. In addition, oral vaccination with liposome-encapsulated DNA vaccine could protect the mice against respiratory challenge infection. These results suggest that gastrointestinal tract, a constituent member of the common mucosal immune system, is a potent candidate applicable as a DNA vaccine route against virus respiratory diseases. © 2013 Wiley Periodicals, Inc.
Lee Y.,Niigata University |
Tsai D.-Y.,Niigata University |
Shinohara N.,Gifu University of Medical Science
Medical Physics | Year: 2010
Purpose: The objective was to develop and investigate an automated scoring scheme of the American College of Radiology (ACR) mammographic accreditation phantom (RMI 156, Middleton, WI) images. Methods: The developed method consisted of background subtraction, determination of region of interest, classification of fiber and mass objects by Mahalanobis distance, detection of specks by template matching, and rule-based scoring. Fifty-one phantom images were collected from 51 facilities for this study (one facility provided one image). A medical physicist and two radiologic technologists also scored the images. The human and computerized scores were compared. Results: In terms of meeting the ACR's criteria, the accuracies of the developed method for computerized evaluation of fiber, mass, and speck were 90%, 80%, and 98%, respectively. Contingency table analysis revealed significant association between observer and computer scores for microcalcifications (p<5%) but not for masses and fibers. Conclusions: The developed method may achieve a stable assessment of visibility for test objects in mammographic accreditation phantom image in whether the phantom image meets the ACR's criteria in the evaluation test, although there is room left for improvement in the approach for fiber and mass objects. © 2010 American Association of Physicists in Medicine.
Mano T.,Gifu University of Medical Science
Acta physiologica Hungarica | Year: 2010
Bone loss is one of the most important complications for astronauts who are exposed to long-term microgravity in space and also for bedridden elderly people. Recent studies have indicated that the sympathetic nervous system plays a role in bone metabolism. This paper reviews findings concerning with sympathetic influences on bone metabolism to hypothesize the mechanism how sympathetic neural functions are related to bone loss in microgravity. Animal studies have suggested that leptin stimulates hypothalamus increasing sympathetic outflow to bone and enhances bone resorption through noradrenaline and β-adrenoreceptors in bone. In humans, even though there have been some controversial findings, use of β-adrenoblockers has been reported to be beneficial for prevention of osteoporosis and bone fracture. On the other hand, microneurographically-recorded sympathetic nerve activity was enhanced by exposure to microgravity in space as well as dry immersion or long-term bed rest to simulate microgravity. The same sympathetic activity became higher in elderly people whose bone mass becomes generally reduced. Our recent findings indicated a significant correlation between muscle sympathetic nerve activity and urinary deoxypyridinoline as a specific marker measuring bone resorption. Based on these findings we would like to propose a following hypothesis concerning the sympathetic involvement in the mechanism of bone loss in microgravity: An exposure to prolonged microgravity may enhance sympathetic neural traffic not only to muscle but also to bone. This sympathetic enhancement increases plasma noradrenaline level and inhibits osteogenesis and facilitates bone resorption through β-adrenoreceptors in bone to facilitate bone resorption to reduce bone mass. The use of β-adrenoblockers to prevent bone loss in microgravity may be reasonable.
Ogata Y.,Nagoya University |
Miyahara H.,Gifu University of Medical Science |
Ishigure N.,Nagoya University |
Ishihara M.,Nagoya City University |
And 2 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2014
A novel sum-peak method was developed to measure samples containing multiple radionuclides. The conventional sum-peak method is one of the absolute radioactivity measurement methods for radionuclides emitting more than one photon in coincidence. The method requires the knowledge of the total count rate as well as the peak count rates and the sum peak count rate. If there are other radionuclides in a sample, it is fraught with difficulty to estimate the total count rate of the nuclide of interest. To solve the problem, a novel calculation method solely using the peak count rates and the sum peak count rate was developed by modifying the conventional sum-peak method. The new method was theoretically verified and experimentally investigated using 60Co and 22Na, and was successfully confirmed. It was proved that the modified sum-peak method is effective to measure samples with multiple radionuclides and is quite simple and practical. © 2014 Elsevier B.V. All rights reserved.
Tanaka K.,Gifu University of Medical Science
VASA. Zeitschrift für Gefässkrankheiten | Year: 2015
BACKGROUND: The second derivative of the finger plethysmogram (SDPTG) comprises five waves termed a to e. The magnitudes of waves b-e are normalized by that of wave a for within- and between-patient comparison. In the present study, affects of meal ingestion for SDPTG in young and elderly subjects are examined.SUBJECTS AND METHODS: Mean arterial pressure and SDPTG before and after meal ingestion in young and elderly subjects were measured. For young subjects, stroke volume and pulse rate were also measured, and the total peripheral resistance (TPR) of the blood vessels was analyzed. Relationship between TPR and the ratio of the peak of SDPTG in young subjects was also analyzed.RESULTS: In young subjects, postprandial d/a was significantly larger and TPR was smaller than before intake and was linearly and significantly correlated with TPR. An increase in the postprandial d/a was also observed in the elderly subjects who were not undergoing hypertension treatment. However, this increase was not observed in elderly subjects who were treated for hypertension.CONCLUSIONS: Change in d/a is considered to be an index of change in TPR. TPR is considered to be decreased by agents for treatment of hypertension, and meal ingestion does not appear to further decrease TPR. These results are considered to be useful for understanding cardiodynamics surrounding meal ingestion.Abstract available from the publisher.
Sugiura A.,Gifu University of Medical Science |
Miyao M.,Nagoya University |
Yamamoto T.,Gifu University of Medical Science |
Takada H.,Gifu University of Medical Science
Displays | Year: 2011
The abnormal contraction of ciliary muscles due to the performance of a near visual task for several hours causes various vision problems such as asthenopia and visual loss. However, these problems can be resolved by activating the muscles by alternately repeating negative and positive accommodation. In this study, we have verified the effect of accommodation training that uses the strategy of presenting a stereoscopic movie to myopic youth and measuring the uncorrected distant visual acuity, spherical diopter (SPH), a flicker test and subjective index of asthenopia obtained using a visual analog scale (VAS). Stereoscopic movies are prepared by using the POWER 3D method (Olympus Visual Communications Co., Ltd.), which reduces the inconsistency between the experienced and the actual senses. Thirty-two myopic students aged 20 ± 1 years (16 males and 16 females) were chosen as the subjects. One group performed the accommodation training for 6 min, and the other group underwent a near visual task during the same period as the control group. We concluded that the accommodation training using a stereoscopic movie had temporarily improved visual acuity. This training seemed to lead to a decrease in asthenopia. © 2011 Elsevier B.V. All rights reserved.
Bernjak A.,Lancaster University |
Cui J.,Nagoya University |
Cui J.,Pennsylvania State University |
Iwase S.,Nagoya University |
And 5 more authors.
Journal of Physiology | Year: 2012
Frequency-domain analyses of simultaneously recorded skin and muscle sympathetic nerve activities may yield unique information on otherwise obscure central processes governing human neural outflows. We used wavelet transform and wavelet phase coherence methods to analyse integrated skin and muscle sympathetic nerve activities and haemodynamic fluctuations, recorded from nine healthy supine young men. We tested two null hypotheses: (1) that human skin and muscle sympathetic nerve activities oscillate congruently; and (2) that whole-body heating affects these neural outflows and their haemodynamic consequences in similar ways. Measurements included peroneal nerve skin and tibial nerve muscle sympathetic activities; the electrocardiogram; finger photoplethysmographic arterial pressure; respiration (controlled at 0.25 Hz, and registered with a nasal thermistor); and skin temperature, sweating, and laser-Doppler skin blood flow. We made recordings at ∼27°C, for ∼20 min, and then during room temperature increases to ∼38°C, over 35 min. We analysed data with a wavelet transform, using the Morlet mother wavelet and wavelet phase coherence, to determine the frequencies and coherences of oscillations over time. At 27°C, skin and muscle nerve activities oscillated coherently, at ever-changing frequencies between 0.01 and the cardiac frequency (∼1 Hz). Heating significantly augmented oscillations of skin sympathetic nerve activity and skin blood flow, arterial pressure, and R-R intervals, over a wide range of low frequencies, and modestly reduced coordination between skin and muscle sympathetic oscillations. These results suggest that human skin and muscle sympathetic motoneurones are similarly entrained by external influences, including those of arterial baroreceptors, respiration, and other less well-defined brainstem oscillators. Our study provides strong support for the existence of multiple, time-varying central sympathetic neural oscillators in human subjects. © 2012 The Authors. Journal compilation © 2012 The Physiological Society.
Shimomura A.,Aichi University |
Takasaki A.,Gifu University of Medical Science |
Nomura R.,Aichi University |
Hayashi N.,Tokyo Institute of Technology |
Senda T.,Aichi University
Medical Molecular Morphology | Year: 2013
Lymphocyte enhancer factor 1 (LEF1), a member of the LEF/T-cell-specific factor (TCF) family of the high mobility group domain transcription factors, acts downstream in canonical Wnt signaling. Aberrant transactivation of LEF1 contributes to the tumorigenesis of colonic neoplasms, sebaceous skin tumors, and lymphoblastic leukemia. LEF1-associated proteins are crucial for regulating its transcriptional activity. In this study, glutathione-S-transferase pull-down assay and mass spectrometry enabled identification of the DNA-dependent protein kinase catalytic subunit (DNA-PKcs) as a novel interaction partner for LEF1. The interaction between LEF1 and DNA-PKcs was confirmed using in vivo co-immunoprecipitation. Furthermore, double immunofluorescence observations showed that LEF1 and DNA-PKcs colocalized in the nuclei of colon adenocarcinoma cell lines. Identification of the interaction between LEF1 and DNA-PKcs may provide clues for a novel therapy for cancer treatment as well as for understanding LEF1-mediated transcriptional regulation. © 2012 The Japanese Society for Clinical Molecular Morphology.