In traumatic brain injury, absent in melanoma 2(AIM2) has been demonstrated to be involved in pyroptotic neuronal cell death. Although the pathophysiological mechanism of spinal cord injury is similar to that of brain...In traumatic brain injury, absent in melanoma 2(AIM2) has been demonstrated to be involved in pyroptotic neuronal cell death. Although the pathophysiological mechanism of spinal cord injury is similar to that of brain injury, the expression and cellular localization of AIM2 after spinal cord injury is still not very clear. In the present study, we used a rat model of T9 spinal cord contusive injury, produced using the weight drop method. The rats were randomly divided into 1-hour, 6-hour, 1-day, 3-day and 6-day(post-injury time points) groups. Sham-operated rats only received laminectomy at T9 without contusive injury. Western blot assay revealed that the expression levels of AIM2 were not significantly different among the 1-hour, 6-hour and 1-day groups. The expression levels of AIM2 were markedly higher in the 1-hour, 6-hour and 1-day groups compared with the sham, 3-day and 7-day groups. Double immunofluorescence staining demonstrated that AIM2 was expressed by NeuN+(neurons), GFAP+(astrocytes), CNPase+(oligodendrocytes) and CD11 b+(microglia) cells in the sham-operated spinal cord. In rats with spinal cord injury, AIM2 was also found in CD45+(leukocytes) and CD68+(activated microglia/macrophages) cells in the spinal cord at all time points. These findings indicate that AIM2 is mainly expressed in neurons, astrocytes, microglia and oligodendrocytes in the normal spinal cord, and that after spinal cord injury, its expression increases because of the infiltration of leukocytes and the activation of astrocytes and microglia/macrophages.展开更多
Carbonyl peroxy radicals (RC(O)O2) are the ubiquitous radical intermediates in the atmospheric oxidation of volatile organic compounds. In this work, theoretical studies are carried out to explore the role of the unim...Carbonyl peroxy radicals (RC(O)O2) are the ubiquitous radical intermediates in the atmospheric oxidation of volatile organic compounds. In this work, theoretical studies are carried out to explore the role of the unimolecular H-migration in the carbonyl peroxy radicals by using quantum chemistry and kinetics calculations. The results showed that H-migration could be significant in the atmosphere at least in CH3CH2CH2C(O)O2 and (CH3)2CHCH2C(O)O2 with rates of ∽0.012 and -0.58^-1 at 298 K. Subsequent reactions of CH3CHCH2C(O)OOH would lead to the products with multi-functional groups, which might affect the aerosol formation process;while (CH3)2CCH2C(O)OOH would transform to formaldehyde and acetone in a few steps. These processes would be important for the atmospheric modelling of volatile organic compounds under low-NOx conditions.展开更多
Apolipoprotein D(ApoD),a member of the lipocalin superfamily of proteins,is involved in lipid transport and stress resistance.Whereas only a single copy of the ApoD gene is found in humans and some other vertebrates,t...Apolipoprotein D(ApoD),a member of the lipocalin superfamily of proteins,is involved in lipid transport and stress resistance.Whereas only a single copy of the ApoD gene is found in humans and some other vertebrates,there are typically several ApoD-like genes in insects.To date,there have been relatively few studies that have examined the evolution and functional differentiation of ApoD-like genes in insects,particularly hemi-metabolous insects.In this study,we identified 10 ApoD-like genes(NlApoD1−10)with distinct spatiotemporal expression patterns in Nilaparvata lugens(BPH),which is an important pest of rice.NlApoD1−10 were found to be distributed on 3 chromosomes in a tandem array of NlApoD1/2,NlApoD3−5,and NlApoD7/8,and show sequence and gene structural divergence in the coding regions,indicating that multiple gene duplication events occurred during evolution.Phylogenetic analysis revealed that NlApoD1−10 can be clustered into 5 clades,with NlApoD3−5 and NlApoD7/8 potentially evolving exclusively in the Delphacidae family.Functional screening using an RNA interference approach revealed that only NlApoD2 was essential for BPH development and survival,whereas NlApoD4/5 are highly expressed in testes,and might play roles in reproduction.Moreover,stress response analysis revealed that NlApoD3−5/9,NlApoD3−5,and NlApoD9 were up-regulated after treatment with lipopolysaccharide,H2O2,and ultraviolet-C,respectively,indicating their potential roles in stress resistance.展开更多
基金supported by the National Natural Science Foundation of China,No.81772321(to HZL),81571194(to HZL),81471277(to JGH)a grant from the Key Program of Anhui Province for Outstanding Talents in Universities in China,No.gxbjZD2016071(to HZL),2014H012(to HZL)
文摘In traumatic brain injury, absent in melanoma 2(AIM2) has been demonstrated to be involved in pyroptotic neuronal cell death. Although the pathophysiological mechanism of spinal cord injury is similar to that of brain injury, the expression and cellular localization of AIM2 after spinal cord injury is still not very clear. In the present study, we used a rat model of T9 spinal cord contusive injury, produced using the weight drop method. The rats were randomly divided into 1-hour, 6-hour, 1-day, 3-day and 6-day(post-injury time points) groups. Sham-operated rats only received laminectomy at T9 without contusive injury. Western blot assay revealed that the expression levels of AIM2 were not significantly different among the 1-hour, 6-hour and 1-day groups. The expression levels of AIM2 were markedly higher in the 1-hour, 6-hour and 1-day groups compared with the sham, 3-day and 7-day groups. Double immunofluorescence staining demonstrated that AIM2 was expressed by NeuN+(neurons), GFAP+(astrocytes), CNPase+(oligodendrocytes) and CD11 b+(microglia) cells in the sham-operated spinal cord. In rats with spinal cord injury, AIM2 was also found in CD45+(leukocytes) and CD68+(activated microglia/macrophages) cells in the spinal cord at all time points. These findings indicate that AIM2 is mainly expressed in neurons, astrocytes, microglia and oligodendrocytes in the normal spinal cord, and that after spinal cord injury, its expression increases because of the infiltration of leukocytes and the activation of astrocytes and microglia/macrophages.
基金supported by the National Key Research Development Program (No.2017YFC0212800)the National Natural Science Foundation of China (No.21477038 and No.21677051)the Natural Science Foundation of Guangdong Province (No.2016A030311005)
文摘Carbonyl peroxy radicals (RC(O)O2) are the ubiquitous radical intermediates in the atmospheric oxidation of volatile organic compounds. In this work, theoretical studies are carried out to explore the role of the unimolecular H-migration in the carbonyl peroxy radicals by using quantum chemistry and kinetics calculations. The results showed that H-migration could be significant in the atmosphere at least in CH3CH2CH2C(O)O2 and (CH3)2CHCH2C(O)O2 with rates of ∽0.012 and -0.58^-1 at 298 K. Subsequent reactions of CH3CHCH2C(O)OOH would lead to the products with multi-functional groups, which might affect the aerosol formation process;while (CH3)2CCH2C(O)OOH would transform to formaldehyde and acetone in a few steps. These processes would be important for the atmospheric modelling of volatile organic compounds under low-NOx conditions.
基金This work was supported by the Natural Science Foundation of Zhejiang Province(LQ22C140001)the National Natural Science Foundation of China(32230086).
文摘Apolipoprotein D(ApoD),a member of the lipocalin superfamily of proteins,is involved in lipid transport and stress resistance.Whereas only a single copy of the ApoD gene is found in humans and some other vertebrates,there are typically several ApoD-like genes in insects.To date,there have been relatively few studies that have examined the evolution and functional differentiation of ApoD-like genes in insects,particularly hemi-metabolous insects.In this study,we identified 10 ApoD-like genes(NlApoD1−10)with distinct spatiotemporal expression patterns in Nilaparvata lugens(BPH),which is an important pest of rice.NlApoD1−10 were found to be distributed on 3 chromosomes in a tandem array of NlApoD1/2,NlApoD3−5,and NlApoD7/8,and show sequence and gene structural divergence in the coding regions,indicating that multiple gene duplication events occurred during evolution.Phylogenetic analysis revealed that NlApoD1−10 can be clustered into 5 clades,with NlApoD3−5 and NlApoD7/8 potentially evolving exclusively in the Delphacidae family.Functional screening using an RNA interference approach revealed that only NlApoD2 was essential for BPH development and survival,whereas NlApoD4/5 are highly expressed in testes,and might play roles in reproduction.Moreover,stress response analysis revealed that NlApoD3−5/9,NlApoD3−5,and NlApoD9 were up-regulated after treatment with lipopolysaccharide,H2O2,and ultraviolet-C,respectively,indicating their potential roles in stress resistance.