Previous studies have found that methylmercury can damage hippocampal neurons and accord- ingly cause cognitive dysfunction. However, a non-invasive, safe and accurate detection method for detecting hippocampal injury...Previous studies have found that methylmercury can damage hippocampal neurons and accord- ingly cause cognitive dysfunction. However, a non-invasive, safe and accurate detection method for detecting hippocampal injury has yet to be developed. This study aimed to detect methylmercury-induced damage on hippocampal tissue using proton magnetic resonance spectroscopy. Rats were given a subcutaneous injection of 4 and 2 mg/kg methylmercury into the neck for 50 consecutive days. Water maze and pathology tests confirmed that cognitive function had been impaired and that the ultrastructure of hippocampal tissue was altered after injection. The results of proton magnetic resonance spectroscopy revealed that the nitrogen-acetyl aspartate/ creatine, choline complex/creatine and myoinositol/creatine ratio in rat hippocampal tissue were unchanged. Therefore, proton magnetic resonance spectroscopy can not be used to determine structural damage in the adult rat hippocampus caused by methylmercury chloride.展开更多
Understanding how natural selection shapes unique traits in mammals is a central topic in evolutionary biology.The mammalian order Chiroptera(bats)is attractive for biologists as well as the general public due to thei...Understanding how natural selection shapes unique traits in mammals is a central topic in evolutionary biology.The mammalian order Chiroptera(bats)is attractive for biologists as well as the general public due to their specific traits of extraordinary immunity and inverted resting posture.However,genomic resources for bats that occupy key phylogenetic positions are not sufficient,which hinders comprehensive investigation of the molecular mechanisms underpinning the origin of specific traits in bats.Here,we sequenced the transcriptomes of 5 bats that are phylo-genetically divergent and occupy key positions in the phylogenetic tree of bats.In combination with the available genomes of 19 bats and 21 other mammals,we built a database consisting of 10918 one-to-one ortholog genes and reconstructed phylogenetic relationships of these mammals.We found that genes related to immunity,bone remodeling,and cardiovascular system are targets of natural selection along the ancestral branch of bats.Further analyses revealed that the T cell receptor signaling pathway involved in immune adaptation is specifically enriched in bats.Moreover,molecular adaptations of bone remodeling,cardiovascular system,and balance sensing may help to explain the reverted resting posture in bats.Our study provides valuable transcriptome resources,enabling us to tentatively identify genetic changes associated with bat-specific traits.This work is among thefirst to advance our understanding of the molecular underpinnings of inverted resting posture in bats,which could provide insight into healthcare applications such as hypertension in humans.展开更多
基金supported by the National Natural Science Foundation of China,No81060231,81160338Hubei Province Natural Science Foundation of China,No.2013CFB277
文摘Previous studies have found that methylmercury can damage hippocampal neurons and accord- ingly cause cognitive dysfunction. However, a non-invasive, safe and accurate detection method for detecting hippocampal injury has yet to be developed. This study aimed to detect methylmercury-induced damage on hippocampal tissue using proton magnetic resonance spectroscopy. Rats were given a subcutaneous injection of 4 and 2 mg/kg methylmercury into the neck for 50 consecutive days. Water maze and pathology tests confirmed that cognitive function had been impaired and that the ultrastructure of hippocampal tissue was altered after injection. The results of proton magnetic resonance spectroscopy revealed that the nitrogen-acetyl aspartate/ creatine, choline complex/creatine and myoinositol/creatine ratio in rat hippocampal tissue were unchanged. Therefore, proton magnetic resonance spectroscopy can not be used to determine structural damage in the adult rat hippocampus caused by methylmercury chloride.
基金supported in part by the National Natural Science Foundation of China(31722051)the National Key Research and Development Program of China(2021YFF0702004)the Fundamental Research Funds for the Central Universities(2042021kf0217)to H.Z.
文摘Understanding how natural selection shapes unique traits in mammals is a central topic in evolutionary biology.The mammalian order Chiroptera(bats)is attractive for biologists as well as the general public due to their specific traits of extraordinary immunity and inverted resting posture.However,genomic resources for bats that occupy key phylogenetic positions are not sufficient,which hinders comprehensive investigation of the molecular mechanisms underpinning the origin of specific traits in bats.Here,we sequenced the transcriptomes of 5 bats that are phylo-genetically divergent and occupy key positions in the phylogenetic tree of bats.In combination with the available genomes of 19 bats and 21 other mammals,we built a database consisting of 10918 one-to-one ortholog genes and reconstructed phylogenetic relationships of these mammals.We found that genes related to immunity,bone remodeling,and cardiovascular system are targets of natural selection along the ancestral branch of bats.Further analyses revealed that the T cell receptor signaling pathway involved in immune adaptation is specifically enriched in bats.Moreover,molecular adaptations of bone remodeling,cardiovascular system,and balance sensing may help to explain the reverted resting posture in bats.Our study provides valuable transcriptome resources,enabling us to tentatively identify genetic changes associated with bat-specific traits.This work is among thefirst to advance our understanding of the molecular underpinnings of inverted resting posture in bats,which could provide insight into healthcare applications such as hypertension in humans.
