The Tohoku Journal of Experimental Medicine
Online ISSN : 1349-3329
Print ISSN : 0040-8727
ISSN-L : 0040-8727
Volume 235 , Issue 2
February
Showing 1-10 articles out of 10 articles from the selected issue
Regular Contribution
  • Chang Shu, Ling Xiao, Jihua Tang, Gaohua Wang, Xueping Zhang, Xiaoping ...
    Type: Regular Contribution
    2015 Volume 235 Issue 2 Pages 81-87
    Published: 2015
    Released: January 21, 2015
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    Childhood adversity has profound and persistent effects on brain functions and has been implicated in the etiology of depression. Brain-derived neurotrophic factor (BDNF) and cAMP response element-binding protein (CREB) play critical roles during brain development to maintain neuronal function and structural integrity in adulthood. We therefore investigated the long-term effects of early life adversity on the depression-related behavior and the expression of BDNF and CREB in the hippocampus. Male Sprague-Dawley newborn rats were subjected to maternal separation for 3 h/day on postnatal days 2-14. After the postnatal day 90, rats with or without the experience of infancy maternal separation received a series of unpredictable chronic mild stress (CMS) for 21 days. Sucrose preference and spontaneous activity in the open field test were recorded, and the expression of BDNF and CREB in the hippocampus was measured by real-time RT-PCR and Western blot analyses. Before exposure to CMS, the rats with maternal separation showed the significant decreases in sucrose preference, spontaneous activity, and hippocampal expression of BDNF and CREB, compared to the animals without maternal separation. In contrast, the rats without maternal separation showed greater decreases of the above indictors after CMS, the levels of which were lower than those observed in the rats with maternal separation. Thus, early life adversity leads to long-term decreases in the capacity of enjoying sweetness, spontaneous activity, and hippocampal expression of BDNF and CREB. Moreover, childhood neglect may decrease the neurobehavioral plasticity, thereby blunting the responses to adulthood stress and increasing the susceptibility to depression.
  • Ken Horibata, Yousuke Takemura
    Type: Regular Contribution
    2015 Volume 235 Issue 2 Pages 89-95
    Published: 2015
    Released: January 30, 2015
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    Elderly patients with less urgent medical needs represent a high proportion of all emergency patients in Japan; this trend is gradually increasing, presenting a burden on the emergency medical system. To design effective interventions, it is important to understand the basic characteristics of emergency service use. For elderly Japanese patients, there is currently no detailed report on less urgent cases (LUC), or those cases that could be diagnosed by primary care physicians. Since there is a need for a timely reporting of detailed LUC data, we used data of 2004-2006 from an immediately available database at the Yao Tokushukai General Hospital. With a focus on LUC, we analyzed 7,800 cases of elderly patients, aged over 65 years, who were transported via ambulance to a secondary emergency hospital in Osaka. Of these, 3,354 patients (43.0%) were classified as having initial emergencies and were given outpatient care in the emergency department, and 1,544 patients (19.8%) were LUC, in which 541 subjects (6.9%) may have used ambulance services somewhat inappropriately owing to a lack of alternate transportation. In the remaining 1,003 patients, ambulance use could have been avoided if primary care clinics were available at night and during holidays. We therefore focus on three important points: awareness-raising activities to prevent inappropriate ambulance use, strengthening of transport services to healthcare facilities, and expanding primary care clinic office hours. This study is the first detailed report on the use of ambulance services in Japan by elderly patients with less urgent medical needs.
Commentary
  • Yasuko Tomizawa
    Type: Commentary
    2015 Volume 235 Issue 2 Pages 97-102
    Published: 2015
    Released: February 05, 2015
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    Japan ranks low in the global gender gap index. Academic promotion is difficult for women doctors, and the leaky pipeline of women doctors is evident in academic medicine. The Japan Surgical Society (JSS) has 2,874 (7.2% of total membership) female members as of April 2014. The total number of councilors in JSS has increased, but there is still only one female member on the Council. The fact that there are so few women in decision-making positions makes it challenging to fight for equality. The Japanese Association of Medical Science (JAMS) is an association with exclusive institutional membership comprising the major medical societies in Japan, and currently has a membership of 122 specialist medical societies. It is essential to have at least one female committee member in each committee of the JAMS, which would provide opportunities to establish career paths for women doctors, to make rules that suit the lifestyle of women doctors, and to improve work-life balance.
Regular Contribution
  • Houyang Chen, Jie Sun, Yuanqiao He, Qianxing Zou, Qiongfang Wu, Yuxin ...
    Type: Regular Contribution
    2015 Volume 235 Issue 2 Pages 103-109
    Published: 2015
    Released: February 06, 2015
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    Testis-specific proteins, synthesized during spermatogenesis and spermiogenesis, are necessary for spermatid differentiation and/or for mature sperm function during fertilization. However, majority of these genes have neither been identified nor fully characterized. Testis developmental related gene 1 (TDRG1), a newly identified human testis-specific gene, encodes a 100-amino-acid protein without any characterized protein domains, and it may play a role in spermatogenesis. However, whether this human-specific protein is important for mature sperm function remains unclear. As an initial effort, in this study, we aimed to systematically investigate the expression and localization of TDRG1 in normal human spermatozoa. Thus, immunohistochemistry was used to analyze the distribution of TDRG1 in human testis. Reverse transcription-polymerase chain reaction, western blot analysis and indirect immunofluorescence were used to determine the expression and localization of TDRG1 in normal human spermatozoa. The immunohistochemistry results showed that the TDRG1 protein was expressed in spermatogenic cells in the seminiferous tubules of human testis. Interestingly, the TDRG1 was more abundant in spermatogenic cells at the late stages of spermatogenesis. The TDRG1 antibody specifically recognized an 11-kDa protein only in soluble extracts from normal human spermatozoa. Indirect immunofluorescence assays indicated that TDRG1 located in the midpiece, principal piece and flagellum of normal human spermatozoa. In conclusion, TDRG1 was found not only in spermatogonia, but also in spermatozoa. The localization of TDRG1 in human normal spermatozoa implies its potential regulatory role in sperm motility.
Perspective
  • Kentaro Tamaki, Nobumitsu Tamaki, Yoshihiko Kamada, Kano Uehara, Hisam ...
    Type: Perspective
    2015 Volume 235 Issue 2 Pages 111-115
    Published: 2015
    Released: February 13, 2015
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    The rate of breast cancer mortality in Okinawa has gradually been increasing up to 2010. Now Okinawa has the second worst mortality rate in Japan, in part due to the enormous dietary changes resulting from the post-World War II US military occupation, high incidence of obesity, high non-optimal treatment rate, and low breast-cancer screening rate. To reduce breast cancer mortality in Okinawa, we established the Okinawa Breast Oncology Meeting (OBOM) in 2012. At the 7th OBOM held on January 10th, 2014, we discussed the breast cancer mortality in Okinawa focusing on lifestyle, breast cancer screening and optimal treatments. The Okinawan women who were overweight and/or obese during premenopausal and postmenopausal ages had a statistically significant higher risk of breast cancer development compared to those with non-overweight and/or obese women. The traditional diet of Okinawa consists of foods low in calories but rich in nutritional value. Therefore, we recommend Okinawan people not to forget the Okinawan traditional lifestyle, and to reduce their bodyweight to prevent breast cancer. One of the main goals of the OBOM is to raise breast cancer screening attendance rates to 50% (29.2% in 2010). We should standardize the quality control for breast cancer screening in Okinawa. It is important to continue enlightening the Okinawan population to receive optimal treatment. In addition, we are striving to establish systematic medical cooperation between the hospitals specializing in breast cancer treatment with rural hospitals. The OBOM group endeavors to contribute to the improvement of breast cancer mortality in Okinawa.
Regular Contribution
  • Tae Sugawara, Naoki Sato, Dai Shimizu, Toshiharu Sato, Kenichi Makino, ...
    Type: Regular Contribution
    2015 Volume 235 Issue 2 Pages 117-125
    Published: 2015
    Released: February 14, 2015
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    Lynch syndrome (LS) is an inherited disorder caused by a germline mutation in the DNA mismatch repair (MMR) genes and is associated with increased risk of various cancers, particularly colorectal cancer and endometrial cancer (EC). It is significant to identify LS in EC patients for prediction and prevention of the succeeding other associated cancers. However, useful LS screening guidelines for EC have not been established. The purpose of our study is to devise an efficient and practical screening strategy for LS in EC. We designed original criteria, named “APF criteria,” with lenient terms (Age of onset < 50, or Personal or Family history of associated cancers) and applied it to unselected EC patients. We performed immunohistochemistry (IHC) and the methylation assay of MutL homolog 1 (MLH1) gene promoter using the tumors of patients who met our criteria, and thus selected “suspected LS” as the candidates for genetic analyses. Of 360 EC patients, 187 (51.9%) met the APF criteria, and the tumor specimens were available from 182 out of the 187 patients. IHC revealed that expression of at least one MMR protein was absent in cell nuclei of 54 (29.6%) tumors. Of 20 tumors lacking MLH1 protein expression, 14 cases were judged sporadic EC because of the hypermethylated MLH1 promoter. We thus selected 40 (11.1%) of 360 EC patients as “suspected LS.” Our strategy that consists of clinical triage and the molecular analyses is expected to improve the screening efficiency and reduce the cost of LS identification in EC.
  • Takao Yaoita, Yu Sasaki, Junji Yokozawa, Takeshi Sato, Nana Kanno, Kaz ...
    Type: Regular Contribution
    2015 Volume 235 Issue 2 Pages 127-134
    Published: 2015
    Released: February 20, 2015
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    The prevalence of colorectal malignancies is increasing in the world. The parallel increase of metabolic syndrome gives a speculation between these two conditions, although the precise mechanism is still unclear. Interleukin-6 (IL-6) is a cytokine known to correlate with obesity and serve as a proinflammatory adipokine. In the present study, we investigated the effect of IL-6 signaling blockade on intestinal polyp formation in obesity using a mouse model of adenomatous polyposis coli (Apc). Male C57BL/6J-ApcMin/+ mice were fed a high-fat diet from 5 weeks of age, and the overweight mice thus obtained were given a weekly intraperitoneal injection of anti-mouse IL-6 receptor antibody (MR16-1) from 6 to 15 weeks of age, while control mice received IgG or phosphate-buffered saline (PBS). The total number of intestinal polyps was significantly decreased in the MR16-1-injected group (53.1 ± 6.8) relative to the control groups (PBS-injected, 81.3 ± 6.1; rat IgG-injected, 74.7 ± 4.8, p = 0.01), and in particular the number of polyps larger than 2 mm in diameter was markedly decreased. In addition, the mean diameter of polyps in the MR16-1-injected group was significantly smaller than that in the control groups. On the other hand, no significant differences in body weight, epididymal fat pad mass, or the plasma levels of glucose, insulin and triglyceride were observed among the three groups. Thus, treatment with anti-IL-6 receptor antibody suppressed polyp growth in obese ApcMin/+ mice fed the high-fat diet. We suggest that IL-6 signaling may be responsible for the obesity-associated colorectal tumorigenesis.
  • Hwa Seong Nam, Su Mi Lee, Eu Gene Jeong, Dong Yeol Lee, Young Ki Son, ...
    Type: Regular Contribution
    2015 Volume 235 Issue 2 Pages 135-144
    Published: 2015
    Released: February 24, 2015
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    Coronary artery disease (CAD) is a primary cause of mortality and morbidity in dialysis patients. However, it is difficult to select the proper point for coronary angiographic procedure, because dialysis patients frequently do not display typical symptoms. Vascular calcification (VC) scores of artery or aorta on plain radiographs are associated with CAD events and may be predictive of CAD in dialysis patients. Therefore, we evaluated whether high or meaningful VC scores on plain radiographs are related with the severity of lesions detected by coronary angiography (CAG) in dialysis patients. We retrospectively enrolled dialysis patients who underwent CAG and checked several plain radiographs within one year before or after CAG. Significant VC is defined as high or meaningful VC scores, such as long abdominal aortic calcification and medial artery calcification on feet. Of all 55 patients, 41 patients (74.5%) exhibited significant VC on plain radiographs and 23 patients (41.8%) underwent stent insertion. Among the 23 patients, longer stents were used in 18 patients with significant VC (34.1 ± 19.5 mm vs. 16.6 ± 15.2 mm, P = 0.029). Patients with significant VC showed higher prevalence rate of severe coronary artery calcification (P = 0.007) and diffuse/tubular stenosis (P = 0.012), detected by CAG, than those without significant VC. Thus, high or meaningful VC scores on plain radiographs were associated with the degree of calcification or stenosis detected by CAG. In conclusion, VC scores on plain radiographs may be predictive of calcification or stenosis of coronary artery before CAG in dialysis patients.
  • Shigeki Koshida, Tetsuo Ono, Shunichiro Tsuji, Takashi Murakami, Kenta ...
    Type: Regular Contribution
    2015 Volume 235 Issue 2 Pages 145-149
    Published: 2015
    Released: February 24, 2015
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    The perinatal mortality rate in Japan has recently been at the lowest level in the world. However, the perinatal mortality rate of Shiga prefecture has been continuously higher than the Japanese average. The reason for this has not yet been explained. The perinatal mortality rate comprises both stillbirths and neonatal deaths. As stillbirths were almost double neonatal deaths, we focused on the stillbirths to determine how they might be prevented. All of the stillbirth certificates in Shiga Prefecture during 2007-2011 were inspected. On the basis of that information, we designed the original questionnaire and sent it to each obstetrician submitting a death certificate to obtain further information associated with the stillbirth. Reviewing retrospectively returned questionnaires by a peer-review team, we evaluated the possibility of preventing stillbirth along with recommendations for prevention. There were 252 stillbirths among 66,682 deliveries in Shiga during this period. We were able to analyze 188 stillbirths (75%). The audit conference judged that 47 cases of them (25%) were determined to have had some possibility of prevention with seven cases (4%) having strong possibility. We identified major causes of preventable stillbirths, including substandard obstetrical management, delayed referral of high-risk women from primary obstetrical clinics to higher perinatal centers, and delayed visits of pregnant women with decreased fetal movements to clinics or hospitals. Based on the results of this study, we conclude that education for pregnant women is required as well as the necessity of improving obstetric care to prevent stillbirths.
  • Tadayuki Tsujita, Shin-ichi Kawaguchi, Takashi Dan, Liam Baird, Toshio ...
    Type: Regular Contribution
    2015 Volume 235 Issue 2 Pages 151-159
    Published: 2015
    Released: February 25, 2015
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    The induction of anti-hypoxic stress enzymes and proteins has the potential to be a potent therapeutic strategy to prevent the progression of ischemic heart, kidney or brain diseases. To realize this idea, small chemical compounds, which mimic hypoxic conditions by activating the PHD-HIF-α system, have been developed. However, to date, none of these compounds were identified by monitoring the transcriptional activation of hypoxia-inducible factors (HIFs). Thus, to facilitate the discovery of potent inducers of HIF-α, we have developed an effective high-throughput screening (HTS) system to directly monitor the output of HIF-α transcription. We generated a HIF-α-dependent reporter system that responds to hypoxic stimuli in a concentration- and time-dependent manner. This system was developed through multiple optimization steps, resulting in the generation of a construct that consists of the secretion-type luciferase gene (Metridia luciferase, MLuc) under the transcriptional regulation of an enhancer containing 7 copies of 40-bp hypoxia responsive element (HRE) upstream of a mini-TATA promoter. This construct was stably integrated into the human neuroblastoma cell line, SK-N-BE(2)c, to generate a reporter system, named SKN:HRE-MLuc. To improve this system and to increase its suitability for the HTS platform, we incorporated the next generation luciferase, Nano luciferase (NLuc), whose longer half-life provides us with flexibility for the use of this reporter. We thus generated a stably transformed clone with NLuc, named SKN:HRE-NLuc, and found that it showed significantly improved reporter activity compared to SKN:HRE-MLuc. In this study, we have successfully developed the SKN:HRE-NLuc screening system as an efficient platform for future HTS.
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