Toshiaki Narasaka

Temporal and spatial distribution of corticosteroidogenic enzymes immunoreactivity in developing human adrenal.

Steroid hormones secreted by fetal adrenocortical cells are considered to be a requirement for a fetus to maintain intrauterine life, but, to date, the regulation of steroid hormone secretion has not been studied in detail in the human fetal adrenal gland. In this study, we examined the immunolocalization of steroidogenic enzymes and their local regulation, including adrenal 4-binding protein (Ad4BP or NR5A1), steroidogenic acute regulatory protein (StAR), P450 cholesterol side-chain cleavage (P450scc or CYP11A1), P450 17alpha-hydroxylase/17,20-lyase (P450c17 or CYP17), 3beta-hydroxysteroid dehydrogenase/isomerase (3beta-HSD), P450 21 hydroxylase (P450c21 or CYP21), dehydroepiandrosterone sulfotransferase (DHEA-ST), P450 oxidoreductase and cytochrome b5, in the human fetal adrenal gland (n=31) obtained from fetuses ranging in ages from 14 to 40 weeks of gestation. Ad4BP immunoreactivity was detected in all adrenocortical zones throughout gestation, suggesting that this nuclear protein is likely to be essential in the development of the human adrenal. Immunoreactivity for StAR, P450scc, P450c21, P450 oxidoreductase and cytochrome b5 was detected only in fetal and transitional zone between 14 and 22 weeks of gestation, but was detected in all three zones after 23 gestational weeks. 3beta-HSD immunoreactivity was not detected in any of the three cortical zones prior to 22 weeks of gestation, but became discernible in the transitional zone and definitive zone after 23 weeks. Immunoreactivity for P450c17 and DHEA-ST was detected in the transitional and fetal zones throughout gestation, but not in the definitive zone. These results suggest that the human adrenal cortex may produce dehydroepiandrosterone (DHEA) in the transitional and fetal zones throughout gestation, and cortisol in the transitional zone after the 23rd week of gestation.

Therapeutic efficacy of the Qing Dai in patients with intractable ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease that may become intractable when treated with conventional medications such as aminosalicylates, corticosteroids, and azathioprine. The herbal medicine Qing Dai has traditionally been used in Chinese medicine to treat UC patients, but there is a lack of published data on the efficacy of Qing Dai in UC treatment. We report several cases of patients with intractable UC who take Qing Dai in a retrospective observational study. Furthermore, we explore the mechanisms of action of Qing Dai. Nine patients with active UC who received conventional medications but wished to receive Qing Dai as an alternative medication were included in our analysis. The UC severity level was determined based on the clinical activity index (CAI). Additionally, 5 of the 9 patients were endoscopically evaluated according to the Matts grading system. Each patient received 2 g/d of Qing Dai orally and continued taking other medications for UC as prescribed. Electron spin resonance was applied to explore the mechanisms of action of Qing Dai. After 4 mo of treatment with Qing Dai, the CAI score decreased from 8.3 ± 2.4 to 2.4 ± 3.4 (mean ± SD; P < 0.001). Similarly, the endoscopic Matts grade decreased from 3.4 ± 0.5 to 2.2 ± 0.8 (P = 0.02). Six of 7 patients who were on prednisolone upon enrollment in the study were able to discontinue this corticosteroid. Electron spin resonance revealed that Qing Dai possesses strong hydroxyl radical scavenging activity. Qing Dai showed significant clinical and endoscopic efficacy in patients who failed to respond to conventional medications. Scavenging of hydroxyl radicals appears to be a potential mechanism through which Qing Dai acts, but the significance of the scavenging ability of Qing Dai with respect to the anti-inflammatory effect in UC patients warrants further investigation.

Significance of fat stains in serial sections from Epon-embedded tissue samples for electron microscopy in renal diseases

AbstractBackground. It is known that abnormal lipid depositions are shown in some renal glomerular diseases. Electron microscopic findings have shown materials with varying degrees of intracytoplasmic electron density, but it has been difficult to prove that they are truly lipids. Methods. Routinely processed Epon-embedded specimens from seven patients with known renal diseases were utilized in this study. Ultrathin sections were cut, and examined by electron microscopy. Then serial 1-μm-thick sections were made stained with Sudan IV. Results. Several patterns of lipid deposition with varying electron densities within the glomeruli were observed by electron microscopy. These lipid depositions were positive for Sudan IV, but showed different colors according to their electron density. Conclusions. The procedure used in the study enables us to recognize light- and electron-microscopic findings of abnormal lipid depositions in serial sections, and may be useful in helping us to simultaneously evaluate the site and nature of these histopathological phenomena.

Endoscopic detachable snare ligation: a new treatment method for colonic diverticular hemorrhage

BACKGROUND AND STUDY AIMS Colonic diverticular hemorrhage is the most common cause of lower intestinal bleeding. We tried to develop a convenient and reliable hemostatic method, endoscopic detachable snare ligation (EDSL), to treat diverticular hemorrhage and retrospectively explored its safety and efficacy. PATIENTS AND METHODS The definitive bleeding diverticulum was ligated with a detachable snare, instead of a rubber band, in a procedure similar to endoscopic band ligation. Removal of the scope to attach a ligation device and reinsertion for treatment are not needed in this method. RESULTS From November 2013 to September 2014, EDSL was used to treat 8 patients with colonic diverticular hemorrhage. The mean procedure time required for hemostasis after identification of the bleeding diverticulum was 5 ± 2 minutes. Sustained hemostasis was achieved in 7 patients (88 %), and early rebleeding occurred in 1 patient, in whom the applied suction seemed inadequate. No complications occurred in any patient. CONCLUSIONS EDSL may be a safe and effective treatment for colonic diverticular hemorrhage. However, additional studies are warranted to confirm these initial exploratory data.

Waterjet submucosal dissection of porcine esophagus with the HybridKnife and ERBEJET 2 system: a pilot study

Background and study aims Esophageal endoscopic submucosal dissection (ESD) is technically difficult because of narrow working spaces and ease of perforation due to the lack of serosa. HybridKnife is a recently developed ESD device that is combined with the high pressure waterjet ERBEJET 2 system to lift mucosa. We hypothesized that this waterjet could make submucosal dissection safer and studied this in porcine esophagus. Materials and methods Water pressures of 30 – 70 bar were tested to determine the appropriate pressure for waterjet ESD with HybridKnife (WJ-ESD) in one pig. WJ-ESD safety and completion were compared with those of conventional ESD using DualKnife (C-ESD) as a reference. Each of three virtual esophageal lesions in two pigs were resected alternatively using both methods from the lower to upper esophagus. For WJ-ESD, the submucosa, apart from hard fibrous tissues, was dissected using water pressure alone. Results Using 50 bar of water pressure resulted in the best balance between proper dissection and view-disturbing water backflow. The dissection speeds for the lower, middle, and upper esophagus were 0.2, 0.9, and 0.2 cm2/min in 50 bar WJ-ESD and 1.1, 0.5, and 1.0 cm2/min in C-ESD, respectively. Minor bleeding was frequent in WJ-ESD, but was easily stopped by electrocoagulation with the same needle. No perforation was observed in either procedure. Thermal damage to dissected tissues appeared mild, and the extent of muscle injury was lower for WJ-ESD (4, 6, and 8 %) compared with C-ESD (14, 16, and 7 %). Conclusions WJ-ESD could be completed safely for porcine esophagus with less damage to the muscle layer compared with C-ESD.

Newly developed endoscopic detachable snare ligation therapy for colonic diverticular hemorrhage: a multicenter phase II trial (with videos)

BACKGROUND AND AIMS We previously reported preliminary safety results for a new method, endoscopic detachable snare ligation (EDSL), for diverticular hemorrhage. This method does not need endoscope removal to attach a ligation device after detection of the bleeding site. The aim of the present study was to evaluate the efficacy and safety of EDSL in a larger patient population. METHODS This prospective study was conducted in 12 institutions. Patients suspected of having diverticular hemorrhage without serious systemic disease were enrolled. The primary endpoint was early (within 30 days) recurrent bleeding rate in patients treated with EDSL. The secondary endpoints were overall early recurrent bleeding rate in patients with definite diverticular bleeding and adverse events in patients treated with EDSL. RESULTS From June 2015 to March 2017, bleeding diverticula were detected in 123 of 205 enrolled patients (60%), of whom 101 (82%) were treated with EDSL. Most patients (20/22) in whom EDSL was not successful were treated with clipping. The early recurrent bleeding rate was 7.9% (95% confidence interval, 2.6%-13.2%; 8/101) in patients who could be treated with EDSL. The median total endoscopic and EDSL procedure time was 40 minutes (interquartile range, 15-71) and 4 minutes (interquartile range, 1-7), respectively. Two mild adverse events, colonic diverticulitis and temporary abdominal pain, were observed. CONCLUSION EDSL was confirmed to be useful and safe for treatment of colonic diverticular hemorrhage. (Clinical trial registration number: UMIN 000001858.).