The Tohoku Journal of Experimental Medicine
Online ISSN : 1349-3329
Print ISSN : 0040-8727
ISSN-L : 0040-8727
Volume 228 , Issue 1
Showing 1-10 articles out of 10 articles from the selected issue
Regular Contributions
  • Yong Soon Park, Jun Su Kim
    2012 Volume 228 Issue 1 Pages 1-8
    Published: 2012
    Released: August 02, 2012
    There is little consensus on the best obesity index associated with metabolic risk factors among the population with normal both body mass index (BMI) and waist circumference (WC). We therefore evaluated the association between anthropometric indices and metabolic risk factors in a Korean population with normal BMI and WC. This cross-sectional study involved 2,952 participants aged 20-79 years who had normal BMI and WC, based on the Fourth Korea National Health and Nutrition Examination Surveys conducted in 2008. The receiver operating characteristic (ROC) curves were generated to identify the optimal measurement of obesity for the prediction of metabolic risk factors in this population. The area under the ROC curve value for waist-to-height ratio (WHtR) in prediction of metabolic syndrome (MetS) and its components was higher than that for BMI and WC. Among individuals with normal BMI and WC, prevalence of all metabolic risk factors and MetS significantly increased across the quartiles of WHtR in both men and women. After adjustment for potential confounders, the Odds Ratios (95% confidence intervals) for MetS in the second, third, and fourth quartiles of WHtR compared to the first quartile of WHtR were 3.53 (2.12-5.89), 6.06 (3.52-10.43), and 7.11 (4.08-12.38) in men, and 1.66 (1.01-2.72), 2.79 (1.81-4.30), and 2.82 (1.76-4.52) in women, respectively. In conclusion, WHtR has the best predictive value for evaluating the metabolic risk factors compared to BMI or WC alone among subjects with normal BMI and WC.
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  • Baiwen Li, Ping Zheng, Qi Zhu, Jun Lin
    2012 Volume 228 Issue 1 Pages 9-16
    Published: 2012
    Released: August 04, 2012
    Accurate staging of gastric cancer is helpful to determine the most appropriate therapy, but no staging modality has been accepted as the standard. Objective is to evaluate the usefulness of endoscopic ultrasonograph (EUS) combined with position emission tomography and computed tomograph (PET-CT) in gastric cancer staging. A total of 124 patients confirmed with gastric cancer were subjected to staging with EUS and PET-CT scanning. The detection rate of primary tumor was 99.2% by combination use of two modalities and 97.6% by EUS alone (p = 0.6219), but the detection rate was 90.3% (112 of 124) by PET-CT alone (compared with the combination, p = 0.0027; compared with EUS alone, p = 0.0299). The locoregional lymph node invasion was identified in 84/124 (67.7%) by combined PET-CT and EUS, which was obviously higher than that with EUS (52.4%) or PET-CT (43.5%) alone (p = 0.0194 and p = 0.0002, respectively). There was no statistical difference in identification of celiac axis lymph node metastasis among three methods, but the combined examination or PET-CT alone was more effective than EUS alone in the detection of distant metastases (all p < 0.01). Furthermore, the combined EUS and PET-CT was more optimal than using EUS or PET-CT alone in the accurate T and N staging and the effect on change of treatment. The present study indicates that the combination of EUS and PET-CT is an ideal modality in the preoperative staging of gastric cancer and it provides beneficial guidance for the treatment of gastric cancer.
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  • Tadaatsu Imaizumi, Tomomi Aizawa-Yashiro, Kazushi Tsuruga, Hiroshi Tan ...
    2012 Volume 228 Issue 1 Pages 17-26
    Published: 2012
    Released: August 11, 2012
    Mesangial cells play an important role in inflammatory reactions in kidney. Although viral infections often trigger the worsening of chronic inflammatory renal diseases, the mechanisms are largely unknown. Melanoma differentiation-associated gene 5 (MDA5) is a member of RNA helicase family with a conserved Asp-Glu-x-His (DExH) box. In the present study, we examined the effect of polyinosinic-polycytidylic acid (poly IC), an authentic double-stranded RNA (dsRNA) that mimics viral dsRNAs, on MDA5 expression using primary culture of human mesangial cells. The cells were simply treated or transfected with poly IC; the former procedure is a model of cells exposed to viral dsRNA released from dying cells, and the latter is a model of entry of RNA virus into the cytoplasm. Expression levels of MDA5 mRNA in mesangial cells were increased about 70-100 fold in response to either treatment or transfection with poly IC. MDA5 protein expression was significantly induced as well. RNA interference experiments revealed that poly IC treatment induced MDA5 expression via Toll-like receptor 3 (TLR3) and interferon (IFN)-β, and that poly IC trasnfection induced MDA5 expression via another DExH box RNA helicase, retinoic acid-inducible gene-I (RIG-I), and IFN-β. Moreover, MDA5 induced by poly IC, in turn, increased the expression of a chemokine CXCL10. In addition, immunohistochemical staining demonstrated a high level of MDA5 expression in glomeruli, mainly in mesangial cells, of patients with severe lupus nephritis or proteinuric IgA nephropathy. MDA5 may be involved not only in physiological antiviral reactions but also in chronic inflammation in glomerular mesangial cells.
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  • Bin Li, Kazuhisa Takeda, Kazunobu Ishikawa, Miki Yoshizawa, Michihiko ...
    2012 Volume 228 Issue 1 Pages 27-41
    Published: 2012
    Released: August 15, 2012
    Heme is an essential requirement for cell survival. Heme oxygenase (HO) is the rate-limiting enzyme in heme catabolism and consists of two isozymes, HO-1 and HO-2. To identify the protein that regulates the expression or function of HO-1 or HO-2, we searched for proteins that interact with both isozymes, using protein microarrays. We thus identified 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 4 (PFKFB4) that synthesizes or degrades fructose-2,6-bisphosphate, a key activator of glycolysis, depending on cellular microenvironments. Importantly, HO-2 and PFKFB4 are predominantly expressed in haploid spermatids. Here, we show a drastic reduction in expression levels of PFKFB4 mRNA and protein and HO-2 mRNA in HepG2 human hepatoma cells in responses to glucose deprivation (≤ 2.5 mM), which occurred concurrently with remarkable induction of HO-1 mRNA and protein. Knockdown of HO-2 expression in HepG2 cells, using small interfering RNA, caused PFKFB4 mRNA levels to decrease with a concurrent increase in HO-1 expression. Thus, in HepG2 cells, HO-1 expression was increased, when expression levels of HO-2 and PFKFB4 mRNAs were decreased. Conversely, overexpression of HO-2 in HepG2 cells caused the level of co-expressed PFKFB4 protein to increase. These results suggest a potential regulatory role for HO-2 in ensuring PFKFB4 expression. Moreover, in D407 human retinal pigment epithelial cells, glucose deprivation decreased the expression levels of PFKFB4, HO-1, and HO-2 mRNAs. Thus, glucose deprivation consistently down-regulated the expression of PFKFB4 and HO-2 mRNAs in both HepG2 cells and RPE cells. We therefore postulate that PFKFB4 and HO-2 are expressed in a coordinated manner to maintain glucose homeostasis.
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  • Li Qi, Zhi-Qiang Zou, Li-Yuan Wang, Shuai Gao, Yu-Chen Fan, Bo Long, Y ...
    2012 Volume 228 Issue 1 Pages 43-51
    Published: 2012
    Released: August 22, 2012
    Chronic hepatitis B (CHB) is a major cause for liver disease worldwide, ranking as the first cause for liver cirrhosis and hepatocellular carcinoma. Acute-on-chronic hepatitis B liver failure (ACHBLF) is most commonly caused by acute severe exacerbation during CHB virus infection. The pathophysiology of ACHBLF is still poorly understood. Glutathione-S-transferase (GST) M3 belongs to GSTs superfamily and it has been demonstrated to contribute to oxidative stress-mediated liver damage. The present study was aimed to determine the potential association between GSTM3 promoter methylation and oxidative stress in ACHBLF patients. Thirty ACHBLF patients, 30 CHB patients and 10 healthy controls were included in this study. Methylation of GSTM3 promoter was determined using methylation-specific PCR (MSP) method. Plasma biomarkers for oxidative stress including malondialdehyde (MDA) and GST were detected by enzyme-linked immunosorbent assay (ELISA). Model for end-stage liver disease (MELD) scoring system was used for predicting the severity and prognosis of liver failure. ACHBLF patients had significant higher GSTM3 promoter methylation rate than CHB patients (30% versus 6.7%, χ2 = 5.455, P = 0.020). Plasma MDA and GST levels were significantly increased in ACHBLF patients compared with CHB patients. Meanwhile, MDA, MELD scores and mortality rate were significantly higher in methylated group than those in unmethylated group of ACHBLF patients. Furthermore, plasma MDA levels were positively correlated with MELD scores of ACHBLF (r = 0.588, P = 0.001). In conclusion, the methylation of GSTM3 promoter may contribute to oxidative stress-associated liver damage and correlate with the disease severity in ACHBLF.
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  • Mieko Uchiyama, Yongbum Lee, Mieko Sadakata, Mitsuko Sayama, Du-Yih Ts ...
    2012 Volume 228 Issue 1 Pages 53-58
    Published: 2012
    Released: August 22, 2012
    Mammography has become widespread as a standard method for breast cancer screening. For women undergoing mammography, compression of the breast and special positioning are requested, and they cause the physical burden and pain. However, the reality of the physical burden and subjective pain associated with mammography are not fully understood. We therefore measured the muscle activity of subjects during positioning for mammography screening using surface electromyography to evaluate the physical burden and pain associated with the positioning. The subjects consisted of 15 women (age: 44.4 ± 6.56 years old, height: 160 ± 6.7 cm, weight: 55.08 ± 3.94 kg, and body mass index: 21.4 ± 2.21). Measurements were performed in the mediolateral oblique position, a standard position for mammography. The target muscles were the sternocleidomastoid, biceps, trapezius and gastrocnemius muscles. A portable multi-purpose bio-amplifier was used for the measurements. Visual analogue scale (VAS), which is a tool for self-assessment of subjective pain, was used for pain measurement. The analysis of variance showed the significant difference in the amounts of muscle activities in all the target muscles between the relaxation phase before mammography positioning and the stress phase during mammography positioning. The sites with the increased muscle activities were consistent with the sites of pain measured with the VAS. These results suggest that positioning during mammography affects the muscle activity and that the increased muscle activity could be related to the pain. Understanding muscle activities during mammography is invaluable in making the pain reduction program for the subjects undergoing mammography.
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  • Yasushi Kudo, Emiko Yoshimura, Machiko Taruzuka Shahzad, Akitaka Shibu ...
    2012 Volume 228 Issue 1 Pages 59-67
    Published: 2012
    Released: August 24, 2012
    In environments in which professional nurses do simple tasks, e.g., laundry, cleaning, and waste disposal, they cannot concentrate on technical jobs by utilizing their expertise to its fullest benefit. Particularly, in Japan, the nursing shortage is a serious problem. If professional nurses take their time to do any of these simple tasks, the tasks should be preferentially allocated to nursing assistants. Because there has been no descriptive study to investigate the amount of time Japanese professional nurses spent doing such simple tasks during their working time, their actual conditions remain unclear. Professional nurses recorded their total working time and the time they spent doing such simple tasks during the week of the survey period. The time an individual respondent spent doing one or more simple tasks during that week was summed up, as was their working time. Subsequently, the percentage of the summed time he or she spent doing any of those tasks in his or her summed working time was calculated. A total of 1,086 respondents in 19 hospitals that had 87 to 376 beds were analyzed (response rate: 53.3%). The average time (SD) that respondents spent doing those simple tasks and their total working time were 2.24 (3.35) hours and 37.48 (10.88) hours, respectively. The average percentage (SD) of the time they spent doing the simple tasks in their working time was 6.00% (8.39). Hospital administrators must decrease this percentage. Proper working environments in which professional nurses can concentrate more on their technical jobs must be created.
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  • Ki Hun Cho, Kyoung Jin Lee, Chang Ho Song
    2012 Volume 228 Issue 1 Pages 69-74
    Published: 2012
    Released: August 30, 2012
    Stroke is one of the most serious healthcare problems and a major cause of impairment of cognition and physical functions. Virtual rehabilitation approaches to postural control have been used for enhancing functional recovery that may lead to a decrease in the risk of falling. In the present study, we investigated the effects of virtual reality balance training (VRBT) with a balance board game system on balance of chronic stroke patients. Participants were randomly assigned to 2 groups: VRBT group (11 subjects including 3 women, 65.26 years old) and control group (11 subjects including 5 women, 63.13 years old). Both groups participated in a standard rehabilitation program (physical and occupational therapy) for 60 min a day, 5 times a week for 6 weeks. In addition, the VRBT group participated in VRBT for 30 min a day, 3 times a week for 6 weeks. Static balance (postural sway velocity with eyes open or closed) was evaluated with the posturography. Dynamic balance was evaluated with the Berg Balance Scale (BBS) and Timed Up and Go test (TUG) that measures balance and mobility in dynamic balance. There was greater improvement on BBS (4.00 vs. 2.81 scores) and TUG (−1.33 vs. −0.52 sec) in the VRBT group compared with the control group (P < 0.05), but not on static balance in both groups. In conclusion, we demonstrate a significant improvement in dynamic balance in chronic stroke patients with VRBT. VRBT is feasible and suitable for chronic stroke patients with balance deficit in clinical settings.
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  • Yuka Yamazaki, Takanori Uka, Haruhiko Shimizu, Akira Miyahira, Tatsuo ...
    2012 Volume 228 Issue 1 Pages 75-82
    Published: 2012
    Released: September 01, 2012
    The number of physicians engaged in basic science and teaching is sharply decreasing in Japan. To alleviate this shortage, central government has increased the quota of medical students entering the field. This study aimed to determine the characteristics of physicians who are engaged in basic science in efforts to recruit talent. A questionnaire was distributed to all 30 physicians in the basic science departments of Juntendo University School of Medicine. Question items inquired about sex, years since graduation, years between graduation and time entering basic science, clinical experience, recommending the career to medical students, expected obstacles to students entering basic science, efforts to inspire students in research, increased number of lectures and practical training sessions on research, and career choice satisfaction. Correlations between the variables were examined using χ2 tests. Overall, 26 physicians, including 7 female physicians, returned the questionnaire (response rate 86.7%). Most physicians were satisfied with their career choice. Medical students were deemed not to choose basic science as their future career, because they aimed to become clinicians and because they were concerned about salary. Women physicians in basic science departments were younger than men. Women physicians also considered themselves to make more efforts in inspiring medical students to be interested in research. Moreover, physicians who became basic scientists earlier in their career wanted more research-related lectures in medical education. Improving physicians' salaries in basic science is important to securing talent. In addition, basic science may be a good career path for women physicians to follow.
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