Primordial germ cells(PGCs),the precursors of oocytes and spermatozoa,are highly pluripotent.In recent years,the in vitro induction of human primordial germ cell-like cells(h PGCLCs)has advanced significantly.However,...Primordial germ cells(PGCs),the precursors of oocytes and spermatozoa,are highly pluripotent.In recent years,the in vitro induction of human primordial germ cell-like cells(h PGCLCs)has advanced significantly.However,the stability and efficacy of obtaining h PGCLCs in vitro still require improvement.In the current study,we identified a novel induction system using Dulbecco's Modified Eagle Medium/Nutrient Mixture F-12(DMEM/F-12)as the basal medium,supplemented with B27 and N2(referred to as N2B27)in combination with four cytokines:bone morphogenetic protein 4,stem cell factor,epidermal growth factor,and leukemia inhibitory factor.The h PGCLCs induced under these conditions closely resembled PGCs from 4-to 5-week-old embryos at the transcriptomic level.Compared with traditional GK15(GMEM supplemented with 15%Knockout?Serum Replacement)-based induction conditions,the N2B27 system significantly increased the speed and efficacy of h PGCLC induction.RNA sequencing analysis revealed that this improvement was due to an increased cellular capacity to cope with hypoxic stress and avoid apoptosis.The N2B27 medium promoted enhanced mitochondrial activity,enabling cells to better manage hypoxic stress while reducing the production of reactive oxygen species.Moreover,through gradient concentration experiments,we demonstrated that the addition of the common antioxidant N-acetyl-L-cysteine at an optimized concentration further enhanced the efficiency of PGCLC induction under GK15 conditions.In summary,we have established an optimized induction system that enhances the efficiency of h PGCLC differentiation by improving cellular resilience to hypoxic stress and apoptosis.展开更多
The equilibrium geometrical optimizations and frequency calculation on B2N2 molecule in the singlet have been made at B3LYP/6-311+G*and CCSD/6-311+G*levels,respectively.The seven stable equilibrium structures were obt...The equilibrium geometrical optimizations and frequency calculation on B2N2 molecule in the singlet have been made at B3LYP/6-311+G*and CCSD/6-311+G*levels,respectively.The seven stable equilibrium structures were obtaind. The rhombus D2h structure of BNBN is the most stable and its electronic state is1A.g.展开更多
The unbalance between synaptic(Glu N2 A, mediating the protective pathway) and extrasynaptic NMDA receptors(NMDARs)(Glu N2 B, mediating the excitotoxic pathway) has been found in Alzheimer disease(AD), indicating rest...The unbalance between synaptic(Glu N2 A, mediating the protective pathway) and extrasynaptic NMDA receptors(NMDARs)(Glu N2 B, mediating the excitotoxic pathway) has been found in Alzheimer disease(AD), indicating restoring the balance of Glu N2 A and Glu N2 B should be beneficial for AD therapy. In this study, the Glu N2 B-selective antagonist, ifenprodil, and the non-selective NMDAR agonist, NMDA, had little effects on amyloid-beta(Abeta)-induced long-term potentiation(LTP) deficits.Enhancing the activity of Glu N2 A had a protective effect against Abeta, and specific activation of Glu N2 A and inhibition of Glu N2 B showed a better protective effect. The combination of ifenprodil and D-cycloserine(a co-activator of NMDRs similar to D-serine) led to greater improvement in behavior tests than ifenprodil or D-cycloserine alone, meanwhile, the combination of ifenprodil and D-cycloserine reversed the signal pathway more significantly than ifenprodil or D-cycloserine alone. These results indicate that enhancing synaptic NMDARs and inhibiting extrasynaptic NMDARs concurrently showed protective effects against Abeta-induced neurotoxicity, suggesting that modulation of the balance between Glu N2 A and Glu N2 B might be a good strategy for drug discovery against AD.展开更多
The aromaticity of all possible substituted fullerene isomers of C18N2, C18B2, C18BN, and their molecular ions which originate from the C20 （Ih） cage were studied by the topological resonance energy （TRE） and the ...The aromaticity of all possible substituted fullerene isomers of C18N2, C18B2, C18BN, and their molecular ions which originate from the C20 （Ih） cage were studied by the topological resonance energy （TRE） and the percentage topological resonance energy methods. The relationship between the aromaticity of C18BxNy isomers and the sites where the heteroatoms dope at the C20 （Ih） cage is discussed. Calculation results show that at the neutral and cationic states all the isomers are predicted to be antiaromatic with negative TREs, but their polyvalent anions are predicted to be aromatic with positive TREs. The most stable isomer is formed by heteroatom doping at the 1,11-sites in C18N2. C18B2, and C18BN. Heterofullerenes are more aromatic than C20. The stability order in the neutral states is C18N2〉C18BN〉C18B2〉C20. The stability order in closed-shell is C18B2^8- 〉C20^6- 〉C18BN^6- 〉C18N2^4-. This predicts theoretically that their polyvalent anions have high aromaticity.展开更多
基金funded by the National Key R&D Program(Grant Nos.2022YFC2702800 and 2021YFC2700302 to Y.Y.)the National Natural Science Foundation of China(Grant Nos.82122025 to Y.Y.,82221005 to J.S.,and 82201763 to L.L.)。
文摘Primordial germ cells(PGCs),the precursors of oocytes and spermatozoa,are highly pluripotent.In recent years,the in vitro induction of human primordial germ cell-like cells(h PGCLCs)has advanced significantly.However,the stability and efficacy of obtaining h PGCLCs in vitro still require improvement.In the current study,we identified a novel induction system using Dulbecco's Modified Eagle Medium/Nutrient Mixture F-12(DMEM/F-12)as the basal medium,supplemented with B27 and N2(referred to as N2B27)in combination with four cytokines:bone morphogenetic protein 4,stem cell factor,epidermal growth factor,and leukemia inhibitory factor.The h PGCLCs induced under these conditions closely resembled PGCs from 4-to 5-week-old embryos at the transcriptomic level.Compared with traditional GK15(GMEM supplemented with 15%Knockout?Serum Replacement)-based induction conditions,the N2B27 system significantly increased the speed and efficacy of h PGCLC induction.RNA sequencing analysis revealed that this improvement was due to an increased cellular capacity to cope with hypoxic stress and avoid apoptosis.The N2B27 medium promoted enhanced mitochondrial activity,enabling cells to better manage hypoxic stress while reducing the production of reactive oxygen species.Moreover,through gradient concentration experiments,we demonstrated that the addition of the common antioxidant N-acetyl-L-cysteine at an optimized concentration further enhanced the efficiency of PGCLC induction under GK15 conditions.In summary,we have established an optimized induction system that enhances the efficiency of h PGCLC differentiation by improving cellular resilience to hypoxic stress and apoptosis.
文摘The equilibrium geometrical optimizations and frequency calculation on B2N2 molecule in the singlet have been made at B3LYP/6-311+G*and CCSD/6-311+G*levels,respectively.The seven stable equilibrium structures were obtaind. The rhombus D2h structure of BNBN is the most stable and its electronic state is1A.g.
文摘The unbalance between synaptic(Glu N2 A, mediating the protective pathway) and extrasynaptic NMDA receptors(NMDARs)(Glu N2 B, mediating the excitotoxic pathway) has been found in Alzheimer disease(AD), indicating restoring the balance of Glu N2 A and Glu N2 B should be beneficial for AD therapy. In this study, the Glu N2 B-selective antagonist, ifenprodil, and the non-selective NMDAR agonist, NMDA, had little effects on amyloid-beta(Abeta)-induced long-term potentiation(LTP) deficits.Enhancing the activity of Glu N2 A had a protective effect against Abeta, and specific activation of Glu N2 A and inhibition of Glu N2 B showed a better protective effect. The combination of ifenprodil and D-cycloserine(a co-activator of NMDRs similar to D-serine) led to greater improvement in behavior tests than ifenprodil or D-cycloserine alone, meanwhile, the combination of ifenprodil and D-cycloserine reversed the signal pathway more significantly than ifenprodil or D-cycloserine alone. These results indicate that enhancing synaptic NMDARs and inhibiting extrasynaptic NMDARs concurrently showed protective effects against Abeta-induced neurotoxicity, suggesting that modulation of the balance between Glu N2 A and Glu N2 B might be a good strategy for drug discovery against AD.
文摘The aromaticity of all possible substituted fullerene isomers of C18N2, C18B2, C18BN, and their molecular ions which originate from the C20 （Ih） cage were studied by the topological resonance energy （TRE） and the percentage topological resonance energy methods. The relationship between the aromaticity of C18BxNy isomers and the sites where the heteroatoms dope at the C20 （Ih） cage is discussed. Calculation results show that at the neutral and cationic states all the isomers are predicted to be antiaromatic with negative TREs, but their polyvalent anions are predicted to be aromatic with positive TREs. The most stable isomer is formed by heteroatom doping at the 1,11-sites in C18N2. C18B2, and C18BN. Heterofullerenes are more aromatic than C20. The stability order in the neutral states is C18N2〉C18BN〉C18B2〉C20. The stability order in closed-shell is C18B2^8- 〉C20^6- 〉C18BN^6- 〉C18N2^4-. This predicts theoretically that their polyvalent anions have high aromaticity.
