We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the...We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the staging of development was based on morphological and physiological characteristics. Two major periods of development were designated： i） early embryonic period, from fertilization to operculum completion stage, lasted for 324 h at water temperature （WT） 18 ？23℃; ii） larval period, from operculum completion stage to tail absorbed stage, took 1207 h at WT 20 ？ 24℃. Tadpoles of the concave-eared torrent frogs showed no evidence of abdominal sucker. Absence of this key characteristic supports the view from molecular systematics that concave-eared torrent frog does not belong to the genus Amolops. Two cleavage patterns were observed in embryos at 8-cell and 16-cell stages, with Pattern I2 （latitudinal cleavage at the 8-cell stage, and meridional cleavage at the 16-cell stage with two perpendicular meridional furrows） being the predominant pattern and only 1.5% belonging to Pattern II （meridional cleavage at the 8-cell stage and latitudinal cleavage at the 16-cell stage）. The factors affecting cleavage and hatching ratios, developmental speed, and ecological adaptation were discussed.展开更多
Torrentophryne aspinia is a new kind of toads discovered in China recently, it lives in the forest floor in West Yunnan, the most important things for this kind of species is that they have a kind of torrent-adapted t...Torrentophryne aspinia is a new kind of toads discovered in China recently, it lives in the forest floor in West Yunnan, the most important things for this kind of species is that they have a kind of torrent-adapted tadpoles which have abdominal suckers and can adhere to the surfaces of rocks in moving waters. In this article, we described the forming procedures of abdominal sucker and some breeding behaviors, habitats and habits. After comparing with those of other toads, it is confirmed that Torrentophryne should be a new valid genus, it is derived from ancestor toads because of adaptation to the torrent habitats, by the forming of torrent -adapted organ-abdominal sucker in the early development.展开更多
Gonad development requires a coordinated soma-germline interaction that ensures renewal and differentiation of germline and somatic stem cells to ultimately produce mature gametes. The Drosophila tumour suppressor gen...Gonad development requires a coordinated soma-germline interaction that ensures renewal and differentiation of germline and somatic stem cells to ultimately produce mature gametes. The Drosophila tumour suppressor gene discs large （dig） encodes a septate junction protein functioning during epithelial polarization, asymmetric neuroblast division, and formation of neuromuscular junctions. Here, we report the role of dig in testis development and its critical function in somatic cyst cells （SCCs）. In these cells dig is primarily required for their survival and expansion, and contributes to spermatocyte cyst differentiation. Cell death primarily occurred in SCCs at the end of spermatogonial amplification at a time when Dig becomes restricted in wild-type （wt） testes to the distal somatic cells capping the growing spermatocyte cysts. RNAi depletion of dig transcripts in early SCCs fully prevented testis development, whereas depletion in late SCCs resulted in a breakdown of spermatocyte cyst structure and germ cell individualization. Specific dig expression in SCCs resulted in developmental rescue of dig mutant testes, whereas its expression in germ cells exerted no such effect, dig overexpression in wt testes led to spermatocyte cyst expansion at the expense of spermatogonial cysts. Our data demonstrate that dig is essentially required in SCCs for their survival, expansion, and differentiation, and for the encapsulation of the germline cells.展开更多
Objective:Polycystic ovary syndrome(PCOS),a common endocrine-metabolic dysfunction in reproductive-aged women,may be involved in compromised pregnancy and offspring outcomes.This study aimed to investigate whether mat...Objective:Polycystic ovary syndrome(PCOS),a common endocrine-metabolic dysfunction in reproductive-aged women,may be involved in compromised pregnancy and offspring outcomes.This study aimed to investigate whether maternal PCOS affects fetal growth,fetal development,and placental features.Methods:This retrospective case-control study included 60 pregnant women with PCOS(PCOS group)and 120 healthy pregnant women without PCOS(control group).Fetal magnetic resonance imaging(MRI)was performed followed by an ultrasound examination and indications for imaging,including known or suspected fetal pathology,history of fetal abnormality in previous pregnancy or in a family member,and concern for placenta accreta.Fetal MRI images were analyzed for head cir-cumference(HC),abdomen circumference(AC),lung-to-liver signal intensity ratio(LLSIR,a prenatal marker of fetal lung maturity),lengths of liver and kidney diameters in fetuses,and placental relative signal intensity on T2-weighted single-shot fast spin echo(SSFSE)imaging(rSISSFSE),and placental relative apparent diffusion coefficient value(rADC).Data on height and weight of offspring were collected through telephone follow-up.Results:Compared to the control group,the PCOS group showed the following characteristics:(1)smaller biparietal diameter and femur length in fetuses(P=0.026 and P=0.005,respectively),(2)smaller HC in fetuses(evident after 32 weeks;P=0.044),(3)lower LLSIR and smaller dorsoventral length of liver in fetuses(evident before 32 weeks;P=0.005 and P=0.019,respec-tively),and(4)smaller placental thickness(evident before 32 weeks;P=0.017).No significant differences in placental rSISSFSE or rADC were observed between the groups(all P>0.05).No significant differences in height and weight of offspring during childhood existed between the groups(all P>0.05).Conclusions:There exist alterations of fetal growth,fetal development,and placental features from women with PCOS.展开更多
基金supported by the National Natural Science Fundation of China(30730029)
文摘We investigated the early embryonic and larval development of the concave-eared torrent frogs, Odorrana tormota （Amphibia, Anura, Ranidae）. Embryos were derived from artificial fertilization of frogs’ eggs, and the staging of development was based on morphological and physiological characteristics. Two major periods of development were designated： i） early embryonic period, from fertilization to operculum completion stage, lasted for 324 h at water temperature （WT） 18 ？23℃; ii） larval period, from operculum completion stage to tail absorbed stage, took 1207 h at WT 20 ？ 24℃. Tadpoles of the concave-eared torrent frogs showed no evidence of abdominal sucker. Absence of this key characteristic supports the view from molecular systematics that concave-eared torrent frog does not belong to the genus Amolops. Two cleavage patterns were observed in embryos at 8-cell and 16-cell stages, with Pattern I2 （latitudinal cleavage at the 8-cell stage, and meridional cleavage at the 16-cell stage with two perpendicular meridional furrows） being the predominant pattern and only 1.5% belonging to Pattern II （meridional cleavage at the 8-cell stage and latitudinal cleavage at the 16-cell stage）. The factors affecting cleavage and hatching ratios, developmental speed, and ecological adaptation were discussed.
文摘Torrentophryne aspinia is a new kind of toads discovered in China recently, it lives in the forest floor in West Yunnan, the most important things for this kind of species is that they have a kind of torrent-adapted tadpoles which have abdominal suckers and can adhere to the surfaces of rocks in moving waters. In this article, we described the forming procedures of abdominal sucker and some breeding behaviors, habitats and habits. After comparing with those of other toads, it is confirmed that Torrentophryne should be a new valid genus, it is derived from ancestor toads because of adaptation to the torrent habitats, by the forming of torrent -adapted organ-abdominal sucker in the early development.
文摘Gonad development requires a coordinated soma-germline interaction that ensures renewal and differentiation of germline and somatic stem cells to ultimately produce mature gametes. The Drosophila tumour suppressor gene discs large （dig） encodes a septate junction protein functioning during epithelial polarization, asymmetric neuroblast division, and formation of neuromuscular junctions. Here, we report the role of dig in testis development and its critical function in somatic cyst cells （SCCs）. In these cells dig is primarily required for their survival and expansion, and contributes to spermatocyte cyst differentiation. Cell death primarily occurred in SCCs at the end of spermatogonial amplification at a time when Dig becomes restricted in wild-type （wt） testes to the distal somatic cells capping the growing spermatocyte cysts. RNAi depletion of dig transcripts in early SCCs fully prevented testis development, whereas depletion in late SCCs resulted in a breakdown of spermatocyte cyst structure and germ cell individualization. Specific dig expression in SCCs resulted in developmental rescue of dig mutant testes, whereas its expression in germ cells exerted no such effect, dig overexpression in wt testes led to spermatocyte cyst expansion at the expense of spermatogonial cysts. Our data demonstrate that dig is essentially required in SCCs for their survival, expansion, and differentiation, and for the encapsulation of the germline cells.
基金Project supported by the National Natural Science Foundation of China(Nos.81874480 and 81873837)the Zhejiang Province Science Foundation for Distinguished Young Scholars(No.LR16H040001),China。
文摘Objective:Polycystic ovary syndrome(PCOS),a common endocrine-metabolic dysfunction in reproductive-aged women,may be involved in compromised pregnancy and offspring outcomes.This study aimed to investigate whether maternal PCOS affects fetal growth,fetal development,and placental features.Methods:This retrospective case-control study included 60 pregnant women with PCOS(PCOS group)and 120 healthy pregnant women without PCOS(control group).Fetal magnetic resonance imaging(MRI)was performed followed by an ultrasound examination and indications for imaging,including known or suspected fetal pathology,history of fetal abnormality in previous pregnancy or in a family member,and concern for placenta accreta.Fetal MRI images were analyzed for head cir-cumference(HC),abdomen circumference(AC),lung-to-liver signal intensity ratio(LLSIR,a prenatal marker of fetal lung maturity),lengths of liver and kidney diameters in fetuses,and placental relative signal intensity on T2-weighted single-shot fast spin echo(SSFSE)imaging(rSISSFSE),and placental relative apparent diffusion coefficient value(rADC).Data on height and weight of offspring were collected through telephone follow-up.Results:Compared to the control group,the PCOS group showed the following characteristics:(1)smaller biparietal diameter and femur length in fetuses(P=0.026 and P=0.005,respectively),(2)smaller HC in fetuses(evident after 32 weeks;P=0.044),(3)lower LLSIR and smaller dorsoventral length of liver in fetuses(evident before 32 weeks;P=0.005 and P=0.019,respec-tively),and(4)smaller placental thickness(evident before 32 weeks;P=0.017).No significant differences in placental rSISSFSE or rADC were observed between the groups(all P>0.05).No significant differences in height and weight of offspring during childhood existed between the groups(all P>0.05).Conclusions:There exist alterations of fetal growth,fetal development,and placental features from women with PCOS.
