The newt genus Tylototriton sensu lato is widely distributed in Eastern,Southeastern and Southern Asia.Previous studies indicated that there still has been several cryptic species in the group.Here,we describe a new s...The newt genus Tylototriton sensu lato is widely distributed in Eastern,Southeastern and Southern Asia.Previous studies indicated that there still has been several cryptic species in the group.Here,we describe a new species of the genus from Guizhou Province,China.Phylogenetic analyses based on mitochondrial DNA supported that the new species was resolved as an independent clade nested into the Tylototriton sensu lato clade.On morphology,the new species could be distinguished from its congeners by a combination of the following characters:large body size(SVL 76.8-85.2 mm in male and 76.3-87.4 mm in female);head longer than wide;snout truncate in dorsal view;tail length longer than the snout-vent length in males;the distal digit ends,ventral digits,peripheral area of cloaca and the tail s lower margin are orange;relative length of toesⅢ> Ⅳ> Ⅱ> Ⅰ> Ⅴ;the distal tips of the limbs greatly overlapping when the fore and hind limbs are pressed along the trunk;fingertips reach the level beyond the snout when the forelimbs are stretched forward.展开更多
Some adult vertebrate species,such as newts,axolotls and zebrafish,have the ability to regenerate their central nervous system（CNS）.However,the factors that establish a permissive CNS environment for correct morphol...Some adult vertebrate species,such as newts,axolotls and zebrafish,have the ability to regenerate their central nervous system（CNS）.However,the factors that establish a permissive CNS environment for correct morphological and functional regeneration in these species are not well understood.Recent evidence supports a role for retinoid signaling in the intrinsic ability of neurons,in these regeneration-competent species,to regrow after CNS injury.Previously,we demonstrated that a specific retinoic acid receptor（RAR）subtype,RARβ,mediates the effects of endogenous retinoic acid（RA）on neuronal growth and guidance in the adult newt CNS after injury.Here,we now examine the expression of the retinoid X receptor RXRα（a potential heterodimeric transcriptional regulator with RARβ）,in newt tail and spinal cord regeneration.We show that at 21 days post-amputation（dpa）,RXRαis expressed at temporally distinct periods and in non-overlapping spatial domains compared to RARβ.Whereas RARβprotein levels increase,RXRαproteins level decrease by 21 dpa.A selective agonist for RXR,SR11237,prevents both this downregulation of RXRαand upregulation of RARβand inhibits tail and caudal spinal cord regeneration.Moreover,treatment with a selective antagonist for RARβ,LE135,inhibits regeneration with the same morphological consequences as treatment with SR11237.Interestingly,LE135 treatment also inhibits the normal downregulation of RXRαin tail and spinal cord tissues at 21 dpa.These results reveal a previously unidentified,indirect regulatory feedback loop between these two receptor subtypes in regulating the regeneration of tail and spinal cord tissues in this regeneration-competent newt.展开更多
We describe a new species of the genus Cynops from northeastern Guangdong, China. This new species is distinguished from its congeners by a combination of morphological and molecular characters. In morphology, it is c...We describe a new species of the genus Cynops from northeastern Guangdong, China. This new species is distinguished from its congeners by a combination of morphological and molecular characters. In morphology, it is chra- cterized by distinctive irregular bluish grey spots on the dorsum from head to tail; irregular, bright orange blotches on venter, chin, underside of axillae, limbs, cloaca; one bright orange stripe in the middle of venter; and ventral tail orange red. Analyses of mitochondrial DNA data indicate that this new species forms one highly diverged lineage within the Chinese group of Cynops.展开更多
The pigmentation in the liver of Chinese fire-bellied newt(Cynops orientalis) was described during two periods of the annual cycle(summer activity and winter hibernation). A large number of melanin granules were gathe...The pigmentation in the liver of Chinese fire-bellied newt(Cynops orientalis) was described during two periods of the annual cycle(summer activity and winter hibernation). A large number of melanin granules were gathered into clusters and distributed unevenly inside the pigment cells. Liver pigmentation(melanin content) was found unstable,varying during the annual cycle. During the hibernation period,pigmentation accumulation was shown to increase in the liver of the Chinese fire-bellied newt. Hepatocytes during the active period are approximately 14.64% larger than those in the hibernation period,while the nucleus is approximately 7.43% bigger during the active period when compared with that during the hibernation period. These findings indicate that variation in pigment distribution and hepatocyte morphology in Chinese fire-bellied newt liver may be an ecologically adaptive strategy to the adverse physiological conditions during hibernation.展开更多
The Chinese fire belly newts （Cynops orientalis） have the ability to escape from the glass tank with vertical walls. An experimental device was developed to investigate the sticking and climbing behaviors of the new...The Chinese fire belly newts （Cynops orientalis） have the ability to escape from the glass tank with vertical walls. An experimental device was developed to investigate the sticking and climbing behaviors of the newts. The detaching angles of the newt on the surfaces of glass, PMMA, and SUS 304 stainless steel at dry, little-water, and plenty-water conditions were meas- ured and used as an index to evaluate the sticking and climbing abilities of the newts on tilted surface. The experimental results show that the newts have a strong ability to stick on tilted surface, particularly on the surface with little water. Morphological studies of the toe pads and belly were carried out by SEM and cryo-SEM to clarify the sticking mechanisms. It is found that the toe pad of the newt consists of a dense array of nanopillars with ca 100 nm - 300 nm diameter surrounded by small channels. This structure is supposed to facilitate high adhesion to substrate by providing capillary forces, and promote the squeeze-out of fluid between the toe pad and substrate in flooded case.展开更多
Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determine...Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determined whether small wetlands, such as pools surrounding fished and fishless lakes, could sustain paedomorphic and metamorphic newts. To this end, we surveyed lakes known historically to sustain Alpine newts Ichthyosaura alpestris as well as 35 nearby pools. On the basis of the published records, the only known population exhibiting paedomorphosis in the Swiss AIps was found to be extirpated by salmonid introductions. However, the metamorphs persisted in per- ipheral pools, paedomorphosis was discovered at a new locality, and overwintering larvae were still present in one of the lakes. These results show the importance of conserving varied aquatic habitats such as pools in mountainous environments where the main resources can become un- suitable for amphibians because of fish introductions. Pools may also function as reservoirs in maintaining newt populations until programs to remove fish from lakes can be carried out. It is not known if paedomorphs could reappear after fish removal. However, the combined resilience of am- phibians after fish removal and the genetic basis for paedomorphosis highlighted in other taxa by previous studies suggest that there is the potential to maintain this intraspecific case of diversity even after its disappearance.展开更多
稀磁半导体兼具半导体材料和磁性材料的双重特性,是破解摩尔定律难题的方案之一.我们团队通过提出自旋和电荷分别掺杂的机制,研制发现了一类新型稀磁半导体材料,为突破经典稀磁半导体材料自旋和电荷一体掺杂引起的材料制备瓶颈提供了有...稀磁半导体兼具半导体材料和磁性材料的双重特性,是破解摩尔定律难题的方案之一.我们团队通过提出自旋和电荷分别掺杂的机制,研制发现了一类新型稀磁半导体材料,为突破经典稀磁半导体材料自旋和电荷一体掺杂引起的材料制备瓶颈提供了有效解决方案.(Ba,K)(Zn,Mn)2As2(BZA)等新型稀磁半导体通过等价掺杂磁性离子引入自旋、异价非磁性离子掺杂引入电荷,实现了 230 K 的居里温度,刷新了可控型稀磁半导体的居里温度记录.本文重点介绍 1)几种代表性的自旋和电荷掺杂机制分离的新型稀磁半导体的发现与研制;2)新型稀磁半导体的子自旋弛豫与高压物性结构的调控;3)大尺寸单晶生长、基于单晶的安德烈夫异质结研制以及自旋极化率的测量.通过新材料设计研制、综合物性研究、简单原型器件构建的“全链条”模式研究,开拓了自旋电荷分别掺杂的稀磁半导体材料研究领域,展现了这类新型稀磁半导体材料潜在的光明前景.展开更多
Peptides (molecular weights are 1200 – 11,600 Da) biologically acting at concentration 10-8 - 10-15 mg/ml were obtained from leaves of dill Anethum graveolens L. and celandine Chelidonium majus L. by circular dichroi...Peptides (molecular weights are 1200 – 11,600 Da) biologically acting at concentration 10-8 - 10-15 mg/ml were obtained from leaves of dill Anethum graveolens L. and celandine Chelidonium majus L. by circular dichroism (CD) spectroscopy. We have shown that these peptides form second structure characterized by the prevalence of β-structures and coil in water solution. In model of organotypic roller culturing of triton liver in vitro, the ability of the peptides isolated from Anethum graveolens L. and Chelidonium majus L. at concentration 10-8 - 10-15 mg/ml to influence increasing of pigment cells, which provided protective function of organism, was demonstrated.展开更多
基金supported by National Natural Science Foundation of China (No.31960099)Basic research project of science and technology department of Guizhou Province (No.[2020]1Y083)+2 种基金Science and technology support project of science and technology department of Guizhou Provincial(No.[2020]4Y029)Guizhou Provincial Department of Education Youth Science and Technology Talents Growth Project (Nos.KY[2018]455 and KY[2018]468)Forestry Science and Technology Research Project of Guizhou Forestry Department (No.[2020]13)。
文摘The newt genus Tylototriton sensu lato is widely distributed in Eastern,Southeastern and Southern Asia.Previous studies indicated that there still has been several cryptic species in the group.Here,we describe a new species of the genus from Guizhou Province,China.Phylogenetic analyses based on mitochondrial DNA supported that the new species was resolved as an independent clade nested into the Tylototriton sensu lato clade.On morphology,the new species could be distinguished from its congeners by a combination of the following characters:large body size(SVL 76.8-85.2 mm in male and 76.3-87.4 mm in female);head longer than wide;snout truncate in dorsal view;tail length longer than the snout-vent length in males;the distal digit ends,ventral digits,peripheral area of cloaca and the tail s lower margin are orange;relative length of toesⅢ> Ⅳ> Ⅱ> Ⅰ> Ⅴ;the distal tips of the limbs greatly overlapping when the fore and hind limbs are pressed along the trunk;fingertips reach the level beyond the snout when the forelimbs are stretched forward.
基金supported by Natural Sciences and Engineering Council of Canada Discovery Grant to RLC and GES
文摘Some adult vertebrate species,such as newts,axolotls and zebrafish,have the ability to regenerate their central nervous system（CNS）.However,the factors that establish a permissive CNS environment for correct morphological and functional regeneration in these species are not well understood.Recent evidence supports a role for retinoid signaling in the intrinsic ability of neurons,in these regeneration-competent species,to regrow after CNS injury.Previously,we demonstrated that a specific retinoic acid receptor（RAR）subtype,RARβ,mediates the effects of endogenous retinoic acid（RA）on neuronal growth and guidance in the adult newt CNS after injury.Here,we now examine the expression of the retinoid X receptor RXRα（a potential heterodimeric transcriptional regulator with RARβ）,in newt tail and spinal cord regeneration.We show that at 21 days post-amputation（dpa）,RXRαis expressed at temporally distinct periods and in non-overlapping spatial domains compared to RARβ.Whereas RARβprotein levels increase,RXRαproteins level decrease by 21 dpa.A selective agonist for RXR,SR11237,prevents both this downregulation of RXRαand upregulation of RARβand inhibits tail and caudal spinal cord regeneration.Moreover,treatment with a selective antagonist for RARβ,LE135,inhibits regeneration with the same morphological consequences as treatment with SR11237.Interestingly,LE135 treatment also inhibits the normal downregulation of RXRαin tail and spinal cord tissues at 21 dpa.These results reveal a previously unidentified,indirect regulatory feedback loop between these two receptor subtypes in regulating the regeneration of tail and spinal cord tissues in this regeneration-competent newt.
基金supported by the grants from the Ministry of Science and Technology of China (MOST Grant 2011FY120200)the National Natural Science Foundation of China (31090250)+1 种基金the Chinese Academy of Sciences (KSCX2YW-Z-0807, KSCX2-EW-Z-2, KSCX2-EW-Q-9)the Bureau of Science and Technology of Yunnan, China (2010CI045)
文摘We describe a new species of the genus Cynops from northeastern Guangdong, China. This new species is distinguished from its congeners by a combination of morphological and molecular characters. In morphology, it is chra- cterized by distinctive irregular bluish grey spots on the dorsum from head to tail; irregular, bright orange blotches on venter, chin, underside of axillae, limbs, cloaca; one bright orange stripe in the middle of venter; and ventral tail orange red. Analyses of mitochondrial DNA data indicate that this new species forms one highly diverged lineage within the Chinese group of Cynops.
基金supported by the initial funding from Henan University of Urban Construction and a grant from the Foundational and Advanced Techniques Foundation of Henan, China (122300410356).
文摘The pigmentation in the liver of Chinese fire-bellied newt(Cynops orientalis) was described during two periods of the annual cycle(summer activity and winter hibernation). A large number of melanin granules were gathered into clusters and distributed unevenly inside the pigment cells. Liver pigmentation(melanin content) was found unstable,varying during the annual cycle. During the hibernation period,pigmentation accumulation was shown to increase in the liver of the Chinese fire-bellied newt. Hepatocytes during the active period are approximately 14.64% larger than those in the hibernation period,while the nucleus is approximately 7.43% bigger during the active period when compared with that during the hibernation period. These findings indicate that variation in pigment distribution and hepatocyte morphology in Chinese fire-bellied newt liver may be an ecologically adaptive strategy to the adverse physiological conditions during hibernation.
文摘The Chinese fire belly newts （Cynops orientalis） have the ability to escape from the glass tank with vertical walls. An experimental device was developed to investigate the sticking and climbing behaviors of the newts. The detaching angles of the newt on the surfaces of glass, PMMA, and SUS 304 stainless steel at dry, little-water, and plenty-water conditions were meas- ured and used as an index to evaluate the sticking and climbing abilities of the newts on tilted surface. The experimental results show that the newts have a strong ability to stick on tilted surface, particularly on the surface with little water. Morphological studies of the toe pads and belly were carried out by SEM and cryo-SEM to clarify the sticking mechanisms. It is found that the toe pad of the newt consists of a dense array of nanopillars with ca 100 nm - 300 nm diameter surrounded by small channels. This structure is supposed to facilitate high adhesion to substrate by providing capillary forces, and promote the squeeze-out of fluid between the toe pad and substrate in flooded case.
文摘Fish introduction is one of the main causes of amphibian decline worldwide. It affects particularly rare aquatic phenotypes such as paedomorphs, which retain gills during the adult stage. In this context, we determined whether small wetlands, such as pools surrounding fished and fishless lakes, could sustain paedomorphic and metamorphic newts. To this end, we surveyed lakes known historically to sustain Alpine newts Ichthyosaura alpestris as well as 35 nearby pools. On the basis of the published records, the only known population exhibiting paedomorphosis in the Swiss AIps was found to be extirpated by salmonid introductions. However, the metamorphs persisted in per- ipheral pools, paedomorphosis was discovered at a new locality, and overwintering larvae were still present in one of the lakes. These results show the importance of conserving varied aquatic habitats such as pools in mountainous environments where the main resources can become un- suitable for amphibians because of fish introductions. Pools may also function as reservoirs in maintaining newt populations until programs to remove fish from lakes can be carried out. It is not known if paedomorphs could reappear after fish removal. However, the combined resilience of am- phibians after fish removal and the genetic basis for paedomorphosis highlighted in other taxa by previous studies suggest that there is the potential to maintain this intraspecific case of diversity even after its disappearance.
文摘稀磁半导体兼具半导体材料和磁性材料的双重特性,是破解摩尔定律难题的方案之一.我们团队通过提出自旋和电荷分别掺杂的机制,研制发现了一类新型稀磁半导体材料,为突破经典稀磁半导体材料自旋和电荷一体掺杂引起的材料制备瓶颈提供了有效解决方案.(Ba,K)(Zn,Mn)2As2(BZA)等新型稀磁半导体通过等价掺杂磁性离子引入自旋、异价非磁性离子掺杂引入电荷,实现了 230 K 的居里温度,刷新了可控型稀磁半导体的居里温度记录.本文重点介绍 1)几种代表性的自旋和电荷掺杂机制分离的新型稀磁半导体的发现与研制;2)新型稀磁半导体的子自旋弛豫与高压物性结构的调控;3)大尺寸单晶生长、基于单晶的安德烈夫异质结研制以及自旋极化率的测量.通过新材料设计研制、综合物性研究、简单原型器件构建的“全链条”模式研究,开拓了自旋电荷分别掺杂的稀磁半导体材料研究领域,展现了这类新型稀磁半导体材料潜在的光明前景.
文摘Peptides (molecular weights are 1200 – 11,600 Da) biologically acting at concentration 10-8 - 10-15 mg/ml were obtained from leaves of dill Anethum graveolens L. and celandine Chelidonium majus L. by circular dichroism (CD) spectroscopy. We have shown that these peptides form second structure characterized by the prevalence of β-structures and coil in water solution. In model of organotypic roller culturing of triton liver in vitro, the ability of the peptides isolated from Anethum graveolens L. and Chelidonium majus L. at concentration 10-8 - 10-15 mg/ml to influence increasing of pigment cells, which provided protective function of organism, was demonstrated.
