Junichi Sugawara

Rare variant discovery by deep whole-genome sequencing of 1,070 Japanese individuals

The Tohoku Medical Megabank Organization reports the whole-genome sequences of 1,070 healthy Japanese individuals and construction of a Japanese population reference panel (1KJPN). Here we identify through this high-coverage sequencing (32.4 × on average), 21.2 million, including 12 million novel, single-nucleotide variants (SNVs) at an estimated false discovery rate of <1.0%. This detailed analysis detected signatures for purifying selection on regulatory elements as well as coding regions. We also catalogue structural variants, including 3.4 million insertions and deletions, and 25,923 genic copy-number variants. The 1KJPN was effective for imputing genotypes of the Japanese population genome wide. These data demonstrate the value of high-coverage sequencing for constructing population-specific variant panels, which covers 99.0% SNVs of minor allele frequency ≥0.1%, and its value for identifying causal rare variants of complex human disease phenotypes in genetic association studies.

Intercellular Adhesion Molecule-1 and Hepatocyte Growth Factor in Human Endometriosis: Original Investigation and a Review of Literature

Defects in the cell-mediated immune system may play a role in the pathogenesis or progression of pelvic endometriosis. Possible mediators include macrophages, interleukins-1 and -6, and tumor necrosis factor-α. More recent work points to the involvement of adhesion molecules and growth factors. To clarify the pathogenesis of endometriosis, we compared the characteristics of soluble intercellular adhesion molecule-1 (soluble ICAM-1) and hepatocyte growth factor (HGF) in women with and without endometriosis. We found that, in patients with endometriosis, the concentrations of soluble ICAM-1 in peritoneal fluid increased and interfered with the activity of natural killer cells. We also found that HGF secretion was significantly increased in cultured endometrial stromal cells, and that HGF stimulated the proliferation and migration of, and morphogenic changes in, endometrial epithelial cells. HGF and ICAM-1 play important roles in the initiation and regulation of endometriotic lesions on the microenvironment level. The increased secretion of HGF by eutopic endometrial stromal cells may contribute to the pathogenesis of endometriosis, whereas the increased levels of soluble ICAM-1 may impair natural killer cell activity and accelerate the progression of the disease.

Increased secretion of hepatocyte growth factor by eutopic endometrial stromal cells in women with endometriosis

OBJECTIVE We evaluated the secretion of hepatocyte growth factor by eutopic endometrial stromal cells in vitro. DESIGN Eutopic endometrial stromal cells were isolated and the culture supernatants were collected after 48 hours of incubation. The secretion of hepatocyte growth factor was analyzed by ELISA. SETTING Department of Obstetrics and Gynecology of Tohoku University Hospital. PATIENT(S) Specimens of endometrium in the proliferative phase were excised from 11 patients who were undergoing laparoscopy for infertility. Six of the patients had endometriosis and five did not. None of the patients had received hormonal treatment before surgery. RESULT(S) Hepatocyte growth factor secretion was found to be increased significantly in cultured endometrial stromal cells from the infertile patients with endometriosis compared with those without endometriosis. CONCLUSION(S) The secretion of hepatocyte growth factor was up-regulated in eutopic endometrial stromal cells from patients with endometriosis. An increase in hepatocyte growth factor production may be characteristic of endometriosis and may be involved in the pathophysiology of this disease.

MicroRNA-34b functions as a potential tumor suppressor in endometrial serous adenocarcinoma

Endometrial serous adenocarcinoma (ESC) is aggressive and carries a poor prognosis. p53 is frequently mutated in ESC. microRNAs (miRNAs) are a direct p53 target and have been implicated in cancer cell behavior. In this study, we compared miRNA expression levels in ESC with the levels in endometrial endometrioid adenocarcinoma (EEC) and normal endometria. Six miRNAs were identified as having aberrant down‐regulation specific to ESC with miR‐34b being most pronounced. miR‐34b was found to have promoter hypermethylation, which when reversed, restored miR‐34b expression in the cell lines treated with 5‐aza‐2′ deoxycytidine (DAC). Ectopic expression of miR‐34b in turn inhibited cell growth, migration and most notably invasion. Our findings suggest a relationship among p53 mutation, miR‐34b promoter methylation and tumor cell behavior. These effects are likely mediated by the downstream target of miR‐34b, the proto‐oncogene mesenchymal‐epithelial transition factor (MET), a known prognostic factor in endometrial carcinomas. The expression of MET was reduced following the restoration of miR‐34b in cell lines. In summary, our data suggest that miR‐34b plays a role in the molecular pathogenesis of endometrial cancer.

The Tohoku Medical Megabank Project: Design and Mission

The Great East Japan Earthquake (GEJE) and resulting tsunami of March 11, 2011 gave rise to devastating damage on the Pacific coast of the Tohoku region. The Tohoku Medical Megabank Project (TMM), which is being conducted by Tohoku University Tohoku Medical Megabank Organization (ToMMo) and Iwate Medical University Iwate Tohoku Medical Megabank Organization (IMM), has been launched to realize creative reconstruction and to solve medical problems in the aftermath of this disaster. We started two prospective cohort studies in Miyagi and Iwate Prefectures: a population-based adult cohort study, the TMM Community-Based Cohort Study (TMM CommCohort Study), which will recruit 80 000 participants, and a birth and three-generation cohort study, the TMM Birth and Three-Generation Cohort Study (TMM BirThree Cohort Study), which will recruit 70 000 participants, including fetuses and their parents, siblings, grandparents, and extended family members. The TMM CommCohort Study will recruit participants from 2013 to 2016 and follow them for at least 5 years. The TMM BirThree Cohort Study will recruit participants from 2013 to 2017 and follow them for at least 4 years. For children, the ToMMo Child Health Study, which adopted a cross-sectional design, was also started in November 2012 in Miyagi Prefecture. An integrated biobank will be constructed based on the two prospective cohort studies, and ToMMo and IMM will investigate the chronic medical impacts of the GEJE. The integrated biobank of TMM consists of health and clinical information, biospecimens, and genome and omics data. The biobank aims to establish a firm basis for personalized healthcare and medicine, mainly for diseases aggravated by the GEJE in the two prefectures. Biospecimens and related information in the biobank will be distributed to the research community. TMM itself will also undertake genomic and omics research. The aims of the genomic studies are: 1) to construct an integrated biobank; 2) to return genomic research results to the participants of the cohort studies, which will lead to the implementation of personalized healthcare and medicine in the affected areas in the near future; and 3) to contribute the development of personalized healthcare and medicine worldwide. Through the activities of TMM, we will clarify how to approach prolonged healthcare problems in areas damaged by large-scale disasters and how useful genomic information is for disease prevention.

Genetic significance of skewed X-chromosome inactivation in premature ovarian failure

To determine the relationship between premature ovarian failure (POF) and skewed X‐chromosome inactivation (XCI), karyotype, and XCI status in 43 patients with POF (group I) and 43 age‐matched control women with regular menstrual cycles (group II) were evaluated. Evaluation of XCI status was based on the CAG triplet repeat polymorphism assay in the androgen receptor gene after sodium bisulfite treatment of DNA samples, and XCI patterns were classified as random (XCI < 70% skewing) or skewed (≥70%). Furthermore, skewed XCI was classified under three different thresholds (≥70, ≥80, or ≥90%). Karyotyping by G‐banding and fluorescence in situ hybridization (FISH) on peripheral blood lymphocytes showed that one patient in group I had a deletion of Xq22, and another was 47,XXX. The frequency of low‐level 45,X/46,XX mosaicism was nearly equal in both groups. In women without any X‐chromosomal aberrations, the incidence of skewed XCI in group I was significantly higher than in group II on all threshold levels. Furthermore, extremely skewed XCI (≥90%) was observed only in group I. These results indicate that POF may be caused by some underlying genetic disorders, which may induce skewed XCI.

Fresh motile testicular sperm retrieved from nonobstructive azoospermic patients has the same potential to achieve fertilization and pregnancy via ICSI as sperm retrieved from obstructive azoospermic patients

OBJECTIVE To compare the fertilization and pregnancy rates using fresh testicular sperm between nonobstructive azoospermic (NOA) patients and obstructive azoospermic (OA) patients. DESIGN We evaluated sperm quality of testicular sperm retrieved by microdissection testicular sperm extraction (MD-TESE) in NOA patients and compared the fertilization rate and pregnancy rate via intracytoplasmic sperm injection (ICSI) between NOA and OA patients. SETTING Private hospital-based infertility research laboratory. PATIENT(S) A total of 58 couples in which the husband was diagnosed with azoospermia. INTERVENTION(S) Analytic examination of the outcomes and description of the NOA cases achieving pregnancies; oocyte retrieval and testicular sperm retrieval were performed simultaneously. MAIN OUTCOME MEASURE(S) Comparison of fertilization rate and pregnancy rate at the first ICSI attempt. RESULT(S) Testicular sperm were retrieved from 17 of 40 NOA patients and 18 of 18 OA patients. Motile sperm were successfully retrieved from 16 of the 17 NOA patients. There was no significant difference in fertilization rate and pregnancy rate between OA and NOA cases. Of the 17 NOA patients, nine pregnancies were achieved using fresh motile testicular sperm. CONCLUSION(S) Fresh motile testicular sperm retrieved from NOA patients may have the same potential to achieve fertilization and pregnancy as sperm retrieved from OA patients. The MD-TESE technique might contribute to the high retrieval rate of fresh motile testicular sperm even in NOA patients.

Intrapartum management guidelines based on fetal heart rate pattern classification

These guidelines provide the recommended response and treatment for intrapartum fetal management based on the classification of FHR patterns, as determined by the Perinatology Committee of the Japan Society of Obstetrics and Gynecology.

Prolonged relaxant effects of vecuronium in patients with deliberate hypermagnesemia : time for caution in cesarean section

We present two cases showing significantly prolonged action of vecuronium from magnesium treatment after general anesthesia for urgent cesarean section. The serum magnesium levels were maintained at a therapeutic range for severe eclampsia in one patient (5.6 mg·dl−1) and for tocolysis in another with placenta previa totalis (6.9 mg·dl−1). The obstetrics-specific emergency in each patient led us to proceed with general anesthesia but using reduced-dose vecuronium, which failed to prevent prolongation of the neuromuscular block. As a result, the patients received prolonged mechanical ventilation. Our cases underscore the need for anesthesiologists as well as obstetricians to be aware of the prolongation of the action of nondepolarizing muscle relaxants as a result of magnesium treatment.

Recent Advances in Fetal Electrocardiography

Since the first observations of Cremer in 1906, fetal electrocardiogram (ECG) measurements via the maternal abdominal wall have remained a formidable challenge for clinical technicians and engineers in the cutting-edge field of information theory. Previous obstacles in extracting fetal ECG still complicate their acquisition at the present. These include three main difficulties for non-invasive measurement of fetal ECG: first, the low signal to noise ratio; second, the lack of a standard lead system for fetal ECG on the maternal abdomen; and third, the factor of fetal movement or non-stationarity during recording. A new extraction system based on blind source separation with reference signals (BSSR) was utilized and our detection rates, both off-line (91%) and on-line (60%), in pregnancies of 20 to 41 weeks of gestation have shown a marked improvement from earlier attempts. With this development, we discuss the potentials and limitations of this new system.