Sex differentiation of gonads in amphibians is believed to be controlled genetically, but altered epigenetically or environmentally. When larvae of the salamander Hynobius retardatus were reared at defined temperatures from hatching to metamorphic stages, a high temperature (28ºC) induced exclusively female gonads (ovaries), whereas intermediate (20 and 23ºC) or lower (16ºC) temperatures produced a 1:1 sex ratio of the morphological gonads. The thermosensitive period was determined to be restricted from 15 to 30 days after hatching, just before or when sexual differentiation occurred. Hynobius P450 aromatase (P450arom) cDNA was isolated from adult gonads and the partial nucleotide or deduced amino acid sequences were determined, showing a high level of identity with various vertebrate species. The P450arom gene was expressed predominantly in the adult ovary and brain, weakly in testis, but not in other somatic organs. A typical sexual dimorphism in P450arom expression was detected in normally developing larvae by a quantitative competitive RT-PCR; strong expression in the female gonads but very weak in male gonads. The dimorphism was detected much earlier than the morphological sexual differentiation of the gonads. When larvae were reared at the female-producing temperature (28ºC), strong expression was detected in all the temperature-treated larvae, suggesting that P450arom was upregulated, even in genetic males. Our results confirm the importance of the P450arom regulation in the sexual differentiation of gonads and demonstrate that an up-regulation of P450arom is involved in the process of temperature-sensitive sex reversal in this species.
Background/Aims: This study aimed at (i) clarifying the factors associated with high scores on the modified frequency scale for the symptoms of gastroesophageal reflux disease (FSSG) among 3,505 relatively healthy subjects undergoing routine medical health checkups with gastrointestinal endoscopy and (ii) comparing risk factors for high FSSG scores between subjects with and without reflux esophagitis. Methods: In total, 3,505 subjects (male/female: 1,922/1,583) who underwent upper gastrointestinal endoscopy during health medical checkups at 5 hospitals in Saga, Japan from January 2013 to December 2013 were enrolled. All subjects completed a modified FSSG questionnaire, which comprised 7 questions regarding reflux symptoms and 7 questions regarding acid-related dyspepsia. Each question was assigned a score based on the frequency of symptoms. Results: Younger age, female gender, hiatal herniation, and endoscopic reflux esophagitis were risk factors for a FSSG score with a high total. Subjects with high scores but without esophagitis were women, and hiatal herniation and Barrett's esophagus were frequently seen in patients with reflux esophagitis. Conclusion: Younger age, female gender, hiatal hernia, and endoscopic esophagitis were risk factors for a high FSSG score, and women tended to complain of upper gastrointestinal symptoms more frequently than did men among subjects without endoscopic esophagitis.
When larvae of the salamander Hynobius retardatus were reared at a high temperature (28°C) during their thermosensitive period (TSP: from 15 to 30 days after hatching), all larvae developed to phenotypic females irrespective of their genetic sexes. Hynobius P450 aromatase (P450arom) and Dmrt-1 cDNAs were isolated and their expression pattern was analyzed by competitive and conventional RT-PCR. While P450arom gene was expressed predominantly in the ovary, Dmrt-1 was expressed exclusively in the testis. When larvae were reared at the female-producing temperature (28°C) during the TSP, strong expression of the P450arom and complete suppression of the Dmrt-1 genes were induced in all experimental larvae. Up-regulation of the P450arom and down-regulation of Dmrt-1 genes even in genetic males constitute a part of the molecular biological cascade for the temperature-dependent sex reversal from genetic males to phenotypic females in this salamander.
Background: The term “acute esophageal mucosal lesion (AEML)” includes black esophagitis, and non-black esophagitis characterized by diffuse circumferential erosions without black-appearing mucosa. Black esophagitis is easily diagnosed, whereas non-black esophagitis is often misdiagnosed as severe reflux esophagitis (sRE). The aim of this study was to determine differences in clinical characteristics of patients with AEML and those with sRE. Methods: Thirty-nine patients with sRE and 32 patients with AEML were diagnosed on the basis of endoscopic findings from 2009 to 2016. Characteristics assessed included age, sex, medication use, coexisting endoscopic finding, comorbidities, laboratory tests results, and chief complaints. Results: In contrast with sRE, male sex, need for emergency endoscopy, presence of duodenal lesions, hypertension, and renal dysfunction were positively associated with AEML. Analysis of associations between laboratory data and AEML showed that high white blood cell count, blood urea nitrogen, and blood glucose were significantly associated with an increase OR for AEML. Conclusions: We showed that AEML differed from sRE regarding both endoscopic findings and clinicopathological features. AEML has not been widely recognized, but it should be defined as a distinct inflammatory disease of the esophagus consisting of both black and non-black esophagitis.
BackgroundThis study aimed to evaluate the influence of Helicobacter pylori infection and its eradication on the upper gastrointestinal symptoms of relatively healthy Japanese subjects.MethodsA total of 3,005 subjects (male/female: 1,549/1,456) undergoing medical health checkups were enrolled in the present study, at five hospitals in Saga, Japan, from January to December 2013. They had no significant findings following upper gastrointestinal endoscopy. All subjects completed a questionnaire that addressed a frequency scale for symptoms of gastroesophageal reflux disease. The questionnaire comprised seven questions regarding reflux symptoms and seven regarding acid-related dyspepsia, which were answered with a score based on the frequency of symptoms. Helicobacter pylori infection was identified by a rapid urease test and/or H. pylori antibody titer, and an eradication history was confirmed by the subjects’ medical records.Results Helicobacter pylori infection was positive in 894 subjects out of 3,005 (29.8%). Eradication of Helicobacter pylori was successfully achieved in 440 subjects of 458 treated. Helicobacter pylori infection had no influence on the acid-related dyspepsia evaluated by the questionnaire, whereas the mean reflux score was relatively high in the Helicobacter pylori native negative subjects compared to Helicobacter pylori native positive. Eradication of Helicobacter pylori and time span after the eradication had no effect on the upper gastrointestinal symptoms evaluated by the questionnaire.Conclusion Helicobacter pylori infection and history of eradication did not affect acid-related dyspepsia symptoms in Japanese healthy subjects.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.