The nomenclature for compounds that are modified with isotopes is growing every day. Compounds can be modified with isotopes either individually, in a functional group or groups, or completely with all atomic centers of the element. This diversity of isotope-modified compounds increases the range of researches that can be studied using them. Compounds modified with isotopes of carbon-13 or nitrogen-15 can be converted into carbon monoxide, carbon dioxide and molecular nitrogen. Currently, only the average value of carbon-13 or nitrogen-15 isotopes can be determined. However, by directly determining the atomic share of these isotopes in organic compounds modified with isotopes, information about the isotopic centers of the element can be obtained. The atomic fraction of an element is defined as a single carbon or nitrogen isotope-modified center or centers, or all centers that are isotope-modified with that element at the same time. Carbon-13 or nitrogen-15 isotopes’ atomic fraction can be determined molecularly or with fragment ions of different elemental content, or both. This makes the method self-verifying, increasing the accuracy and reliability of the results obtained. Amino acids, such as asparagine, aspartic acid, methionine, and threonine, are essential for the human body. This proposed method of isotopic analysis will increase the possibilities for scientific research using these compounds.
The current study aimed to compare the effects of increasing concentrations of dietary threonine(Thr),tryptophan(Trp),and glycine(Gly)on growth performance,stress biomarkers,and intestinal function in broiler chickens under multiple stress conditions.Five hundred sixty broiler chickens at 21 d old were randomly allotted to 5 treatments with 8 replicates.Birds in a positive control(PC)treatment were raised under low stock density(16.9 birds/m^(2) per cage)with recommended environmental conditions,whereas birds in 4 treatments were subjected to multiple stress conditions:a cyclic heat stress of 30±0.3℃ for 10 h and 23±0.2℃ for 14 h per day with high stock density(25.3 birds/m^(2) per cage).A basal diet was assigned to both PC and negative control(NC)treatments.Three additional diets were individually formulated to contain double concentrations of digestible Thr,Trp,or Gly+Ser compared with their concentrations in the basal diet.The experiment lasted for 14 d.Results showed that NC treatment had less growth performance(P<0.001),jejunal goblet cell counts(P=0.018),and trans-epithelial electrical resistance(TEER;P<0.001),but greater(P=0.026)feather corticosterone(CORT)concentrations than PC treatment.Thr treatment showed the least(P<0.001)feed conversion ratio(FCR)among treatments under multiple stress conditions.Thr,Trp,and Gly treatments had less(P=0.026)feather CORT concentrations,but had greater(P<0.001)TEER than NC treatment.In conclusion,increasing concentrations of dietary Thr,Trp,or Gly improve the growth performance and intestinal health in broiler chickens with decreasing stress response under multiple stress conditions.
The associations of individual amino acid with non-alcoholic fatty liver disease(NAFLD)risk remained unclear.The present study aimed to investigate the associations between the two in the Chinese elderly.Methods:A community-based health check-up program was conducted in Qingdao,China.NAFLD was diagnosed by ultrasonography accompanied by epidemiological investigation.The dietary intakes of amino acids were investigated with 3-day,24-h dietary records and calculated by Nutrition Calculator software.Restricted cubic spline model was used to evaluate a nonlinear relationship between amino acid intake and NAFLD risk.Results:400 NAFLD subjects were identified,and 400 participants were randomly selected as controls and matched by gender and age(±3 years)Dose-response analysis showed that 1000 mg increment of aromatic amino acids(AAAs)was associated with reduced 16%risk of NAFLD.Dietary increments of 750 mg/d threonine,950 mg/d valine,or 1700 mg/d lysine were associated with a 20%reduction in the NAFLD risk(all P for linearity<0.05).Conclusion:The present study demonstrated that the dietary increases in milk,eggs and deep-sea fish,which are rich in the amino acids,might contribute to protecting against NAFLD in the elderly.
目的:本研究旨在比较维莫非尼联合考比替尼、达拉非尼联合曲美替尼和康奈非尼联合贝美替尼3种丝氨酸/苏氨酸蛋白激酶(serine/threonine-protein kinase B-raf,BRAF)/丝裂原活化蛋白激酶(mitogen-activated protein kinases,MEK)联合抑制剂间药品不良反应(adverse drug reaction,ADR)的差异,以期指导临床安全用药。方法:收集2011年第1季度—2023年第2季度美国FDA不良事件报告系统中的ADR报告,使用报告比值比法和贝叶斯可信区间递进神经网络法进行数据分析,同时采用Chi-square统计方法对组间数据进行分析。结果:研究共纳入17982份ADR报告,其中达拉非尼联合曲美替尼报告数最多,为12746份,且报告死亡结局的比例(26.62%)也高于其他方案组。3种治疗方案主要累及系统器官分别为皮肤及皮下组织类疾病、全身性疾病及给药部位各种反应和胃肠系统疾病。在维莫非尼联合考比替尼和康奈非尼联合贝美替尼方案中,浆液性视网膜病关联性最强,维莫非尼联合考比替尼方案发生器质性脑综合征ADR致死概率为100.00%。结论:临床上应关注维莫非尼联合考比替尼方案发生器质性脑综合征ADR致死风险,不同BRAF/MEK联合抑制剂与特定系统器官的ADR关联强度存在差异,临床医生可根据患者的具体需求合理选择药物,并对ADR进行有效监测。