Nucleotide second messengers are highly versatile signaling molecules that regulate a variety of key biological processes in bacteria.The best-studied examples are cyclic AMP(cAMP)and bis-(3'-5')-cyclic dimeric guanosine monophosphate(c-di-GMP),which both act as global regulators.Global regulatory frameworks of c-di-GMP and cAMP in bacteria show several parallels but also significant variances.In this review,we llustrate the global regulatory models of the two nucleotide second messengers,compare the different regulatory frameworks between c-di-GMP and cAMP,and discuss the mechanisms and physiological significance of cross-regulation between c-di-GMP and cAMP.c-di-GMP responds to numerous signals de-pendent on a great number of metabolic enzymes,and it regulates various signal transduction pathways through its huge number of effectors with varying activities.In contrast,due to the limited quantity,the cAMP metabolic enzymes and its major effector are regulated at different levels by diverse signals.cAMP performs its global regulatory function primarily by controlling the transcription of a large number of genes via cAMP receptor protein(CRP)in most bacteria.This review can help us understand how bacteria use the two typical nucleotide second messengers to effectively coordinate and integrate various physiological processes,providing theoretical guidelines for future research.
Cong LiuRui ShiMarcus S.JensenJingrong ZhuJiawen LiuXiaobo LiuDi SunWeijie Liu
目的对1例高频抗体导致的胎儿新生儿溶血病(hemolytic disease of the fetus and newborn,HDFN)进行检测、鉴定及配血。方法对患儿进行新生儿溶血试验,对母亲进行血清学意外抗体鉴定,并对母亲红细胞进行常见高频抗原鉴定;对检出抗体进行IgG分型检测,并用流式细胞术进行单核细胞体外吞噬致敏红细胞试验,以检测抗体相关的吞噬率;对患儿母亲、父亲及舅舅进行相关红细胞血型基因测序;利用稀释的母亲血浆和抗人球卡法,在献血者中进行大规模相合血液的筛选。结果产妇鉴定为Di(b-)稀有血型,产生了抗-Di b(效价512)并导致了严重的HDFN;抗-Di b亚型分型为IgG1和IgG2型,单核细胞体外吞噬效率为88.83%(74.7/84.09);产妇亲属中没有相合献血者,后续从5520名献血者中筛选到2例Di(b-)相合血液,患儿接收输血治疗后康复出院。后续在51334名献血者中筛查到17名Di(b-)献血者,该数据表明Di(b-)在广州地区献血者中的分布频率约为三千分之一(0.033%,17/51334)。结论综合利用血型血清学及分子生物学方法诊断了抗-Di b所致的严重HDFN,建立了1种有效大规模筛查Di(b-)稀有血型的方法并找到相合血液,为建立Di(b-)稀有血型库奠定了基础。
Huang Di Nei Jing(《黄帝内经》The Yellow Emperor’s Inner Classic) has been the source text of Chinese medicine knowledge and innovation for over two thousand years. Despite this key relevance, many of its ideas and practices have proven difficult to understand and implement fully into clinical practice. Cultural and language differences can be compounded with these challenges but may also present new opportunities for advancement and insight when studied by researchers outside of the originating culture. This article introduces the method of Classical-Text Archaeology and delves into the author’s two-decade journey of researching this text, with a discussion on cultural differences and issues of medical scholarship.
