A5101976114- Reproductive biology and impacts on aquatic species
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Aquaculture Nutrition and Growth
- Schizophrenia research and treatment
- Sperm and Testicular Function
- Fish Ecology and Management Studies
- Ichthyology and Marine Biology
- Marine and coastal plant biology
- Echinoderm biology and ecology
- Bipolar Disorder and Treatment
- Animal Genetics and Reproduction
- Diet and metabolism studies
- Physiological and biochemical adaptations
- Marine Bivalve and Aquaculture Studies
- Tryptophan and brain disorders
- Marine Biology and Environmental Chemistry
- Hormonal and reproductive studies
- Gastrointestinal motility and disorders
- Electroconvulsive Therapy Studies
- Marine and fisheries research
- Helicobacter pylori-related gastroenterology studies
- Coral and Marine Ecosystems Studies
- Animal Behavior and Reproduction
- Pharmacological Effects and Toxicity Studies
- Electrolyte and hormonal disorders
Okinawa Churashima Foundation
2014-2024
Tokatsu Hospital
2022
GTx (United States)
2021
Otsuka (Japan)
1994-2021
University of the Ryukyus
2004-2018
Sartorius (United States)
2018
University of California San Francisco Medical Center
2017
Saitama Medical University
2012-2017
Sapporo City General Hospital
2016
Bio-oriented Technology Research Advancement Institution
2008
The Nile tilapia, a gonochoristic teleost fish with an XX/XY sex-determining system, provides excellent model for studying gonadal sex differentiation because genetic all-females and all-males are available. In this study, we used quantitative real-time RT-PCR to determine the precise timing of expression 17 genes thought be associated in vertebrates. Gonads were isolated from all-female all-male tilapia before (5-15 days after hatching [dah]) (25-70 dah) morphological differentiation....
Abstract This study investigated whether undifferentiated germ and/or somatic stem cells remain in the differentiated ovary of a species that does not undergo sex changes under natural conditions and retain their sexual plasticity. The effect aromatase inhibitor (AI)-treatment on sexually mature female zebrafish was examined. A 5-month AI treatment caused retraction ovaries after which testes-like organs appeared cyst structures filled with spermatozoa-like were observed sections these...
In order to identify the dominant contributors estrogenic activity in environmental waters, a comprehensive fractionation method using silica gel column chromatography, combined with recombinant yeast assay for detecting and gas chromatography-mass spectrometry quantifying endocrine disruptors natural estrogens, was developed. The applied municipal sewage treatment plant (STP) secondary effluent discharged Tamagawa River Tokyo, Japan, where disruption observed wild carp. instrumental...
The honeycomb grouper shows protogynous hermaphroditism. endocrine mechanisms involved in gonadal restructuring throughout sex change are largely unknown. In the present study, we investigated changes structures and levels of serum steroid hormones during female to male grouper. On basis histological changes, entire process was assigned into four developmental phases: female, early transition (ET), late (LT), phase. At phase, oocytes several stages were observed including gonial germ cells...
Steroid hormones have been shown to play important roles in triggering sex change. However, the upstream mechanism that regulates secretion of steroid controlling change is not yet known. Cortisol, primary glucocorticoid teleost fish, known exhibit anti-stress action and involved many physiological functions, including regulation steroidogenesis. Therefore, cortisol could be one candidate factors onset In this study, we investigated role three-spot wrasse, <i>Halichoeres...
In order to examine the initial appearance and development of steroid producing cells (SPCs) during process ovarian differentiation, histology ultrastructure tilapia (Sarotherodon niloticus) ovaries were investigated from 10 50 days after hatching. gonads fry at 23-26 hatching, differentiation was confirmed by stromal aggregations in proximal distal region gonad on side facing lateral wall. This represents formation cavity. At same time as a few large appeared initially vicinity blood...
Abstract The protogynous hermaphrodite fish change sex from female to male at the certain stages of life cycle. endocrine mechanisms involved in gonadal restructuring throughout are not clearly understood. In present study, we implanted maturing honeycomb groupers with nonsteroidal aromatase inhibitor (AI), Fadrozole (0, 1, and 10 mg/fish) examined changes structures serum levels steroid hormones 2½ months after implantation. ovaries control females had oocytes undergoing active...
Protandrous black porgy fish, Acanthopagrus schlegeli, have a striking life cycle, with male sex differentiation at the juvenile stage, bisexual gonad during first 2 yr of life, and male-to-female change (with vitellogenic oocytes) 3 age. The present study investigated role aromatase (cyp19a1a/Cyp19a1a) in gonadal development this species, especially relation to sexual change. Fish various ages were treated estradiol (E2) or inhibitor (AI) determine whether manipulation hormonal environment...
ABSTRACT The great white shark (Carcharodon carcharias) exhibits viviparous and oophagous reproduction. A 4950 mm total length (TL) gravid female accidentally caught by fishermen in the Okinawa Prefecture, Southern Japan carried six embryos (543-624 TL, three each uterus). Both uteri contained copious amounts of yellowish viscous uterine fluid (over 79.2 litres left uterus), nutrient eggs broken egg cases. had yolk stomachs that ruptured, mean volume which was approximately 197.9 ml. Embryos...
Abstract Background Near-infrared spectroscopy (NIRS) has been approved as an insurance-covered auxiliary laboratory test for differential diagnosis of depressive state in Japan. However, reports indicated a certain mismatching rate between psychiatric and NIRS waveform pattern, which may be due to age-related decline cortical activity, various clinical stages, dose-dependent impact psychotropic drugs, individual biological conditions on signals. Aim To investigate the relationship...
Sex determination has been investigated across vertebrate lineages to reveal stepwise evolution of sex chromosomes and diversity responsible molecular mechanisms. However, these studies hardly encompass cartilaginous fishes deeply isolated from the rest vertebrates, which hinders comprehensive view determination. Here, we produced chromosome-scale genome assemblies egg-laying shark species comparatively sequences transcriptome profiles diverse fishes. chromosome identification, supported by...
The incidence of the tethered cord syndrome after repair spinal dysraphism is not insignificant. A retethered may also develop an untethering operation. In order to treat and/or prevent and cord, authors developed successfully used a new method in 12 cases. After complete release reconstruction Gore-Tex surgical membrane was placed over fixed lateral dural surface with stay sutures. During postoperative follow-up period ranging from 23 months 7 years, no further neurological deterioration...
Circulating estradiol–17β (E2) levels decrease precipitously during female to male (protogynous) sex change in fish. Whether this drop E2 is a cause or consequence of still largely unknown. The present study treated adult honeycomb groupers (Epinephelus merra) with aromatase inhibitor (AI, Fadrozole), either alone combination E2, investigate the role estrogen protogynous change. Control fish had ovaries undergoing active vitellogenesis; gonads AI-treated already developed into testes, which...